You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
blabla/PATSTAT/CPC_data/CPCSchemeXML202302/cpc-scheme-H04R.xml

367 lines
204 KiB
XML

<?xml version="1.0" encoding="UTF-8"?>
<class-scheme publication-date="2023-02-01" scheme-type="cpc" publication-type="official">
<classification-item breakdown-code="false" not-allocatable="true" level="5" additional-only="false" sort-key="H04R" definition-exists="true" date-revised="2018-08-01" status="published"><classification-symbol>H04R</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS</text></title-part><title-part><text>DEAF-AID SETS</text></title-part><title-part><text>PUBLIC ADDRESS SYSTEMS </text><reference><text>generating mechanical vibrations in general <class-ref scheme="cpc">B06B</class-ref>; transducers for measuring particular variables <class-ref scheme="cpc">G01</class-ref>; transducers in clocks <class-ref scheme="cpc">G04</class-ref>; producing sounds with frequency not determined by supply frequency <class-ref scheme="cpc">G10K</class-ref>; transducers in recording or reproducing heads <class-ref scheme="cpc">G11B</class-ref>; transducers in motors <class-ref scheme="cpc">H02</class-ref></text></reference></title-part></class-title><notes-and-warnings date-revised="2013-01-01"><note type="note"><note-paragraph> This subclass <u>covers</u> : <subnote type="bullet"><note-paragraph> loudspeakers, microphones, <CPC-specific-note>acoustic</CPC-specific-note> transducers <CPC-specific-note>therefor</CPC-specific-note> producing acoustic waves or variations of electric current or voltage, or gramophone pick-ups; </note-paragraph><note-paragraph>arrangements actuated by variations of electric current or voltage for cutting grooves in records;</note-paragraph><note-paragraph> circuits for the above-mentioned <CPC-specific-note>loudspeakers, microphones, acoustic transducers, gramophone pick-ups or</CPC-specific-note> arrangements; </note-paragraph><note-paragraph> monitoring or testing <CPC-specific-note>of the above-mentioned loudspeakers, microphones, acoustic transducers, gramophone pick-ups or arrangements</CPC-specific-note></note-paragraph></subnote></note-paragraph></note><note type="warning"><note-paragraph>In this subclass non-limiting references (in the sense of paragraph 39 of the Guide to the IPC) may still be displayed in the scheme.</note-paragraph></note></notes-and-warnings>
<classification-item breakdown-code="false" not-allocatable="true" level="6" additional-only="false" sort-key="H04R1/00" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/00</classification-symbol>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R1/00" definition-exists="true" ipc-concordant="H04R1/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details of transducers, </text><CPC-specific-text><text>loudspeakers or microphones</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/005" definition-exists="true" ipc-concordant="H04R1/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/005</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using digitally weighted transducing elements</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/02" definition-exists="true" ipc-concordant="H04R1/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2017-08-01" status="published"><classification-symbol>H04R1/02</classification-symbol><class-title date-revised="2017-08-01"><title-part><text>Casings</text></title-part><title-part><text>Cabinets </text><CPC-specific-text><text>; Supports therefor;</text></CPC-specific-text><text> Mountings therein </text><reference><text><class-ref scheme="cpc">H04R1/28</class-ref> takes precedence </text><CPC-specific-text><text>; attachments for microphones <class-ref scheme="cpc">H04R1/08</class-ref>; mounting of transducers in earpieces <class-ref scheme="cpc">H04R1/1075</class-ref></text></CPC-specific-text></reference></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/021" definition-exists="false" ipc-concordant="H04R1/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/021</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>incorporating only one transducer</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/023" definition-exists="true" ipc-concordant="H04R1/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/023</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Screens for loudspeakers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/025" definition-exists="true" ipc-concordant="H04R1/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/025</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Arrangements for fixing loudspeaker transducers, e.g. in a box, furniture</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/026" definition-exists="true" ipc-concordant="H04R1/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/026</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Supports for loudspeaker casings</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/028" definition-exists="false" ipc-concordant="H04R1/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/028</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>associated with devices performing functions other than acoustics, e.g. electric candles</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/04" definition-exists="true" ipc-concordant="H04R1/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Structural association of microphone with electric circuitry therefor </text><reference><text>in deaf-aid sets <class-ref scheme="cpc">H04R25/00</class-ref></text></reference></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/06" definition-exists="true" ipc-concordant="H04R1/06" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/06</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Arranging circuit leads</text></title-part><title-part><text>Relieving strain on circuit leads</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/08" definition-exists="true" ipc-concordant="H04R1/08" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2017-08-01" status="published"><classification-symbol>H04R1/08</classification-symbol><class-title date-revised="2017-08-01"><title-part><text>Mouthpieces</text></title-part><title-part><CPC-specific-text><text>Microphones;</text></CPC-specific-text><text> Attachments therefor</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/083" definition-exists="false" ipc-concordant="H04R1/08" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/083</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Special constructions of mouthpieces</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/086" definition-exists="true" ipc-concordant="H04R1/08" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/086</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Protective screens, e.g. all weather or wind screens</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/10" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2017-08-01" status="published"><classification-symbol>H04R1/10</classification-symbol><class-title date-revised="2017-08-01"><title-part><text>Earpieces</text></title-part><title-part><text>Attachments therefor </text><CPC-specific-text><text>; Earphones; Monophonic headphones </text><reference><text><class-ref scheme="cpc">H04R1/28</class-ref> takes precedence; stereophonic headphones <class-ref scheme="cpc">H04R5/033</class-ref></text></reference></CPC-specific-text></title-part></class-title><notes-and-warnings date-revised="2013-01-01"><note type="note"><note-paragraph>This group <u>covers</u> details of headphones, both of monophonic and stereophonic type. </note-paragraph><note-paragraph>When classifying in this group or in its subgroups, aspects relating to stereophonic headphones are to be classified in <class-ref scheme="cpc">H04R5/033</class-ref> as well </note-paragraph></note></notes-and-warnings>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/1008" definition-exists="false" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/1008</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Earpieces of the supra-aural or circum-aural type</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/1016" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/1016</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Earpieces of the intra-aural type</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/1025" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/1025</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Accumulators or arrangements for charging </text><reference><text>secondary cells <u>per se</u> <class-ref scheme="cpc">H01M10/00</class-ref>; charging in general <class-ref scheme="cpc">H02J7/00</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/1033" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/1033</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Cables or cables storage, e.g. cable reels </text><reference><text>cord reels <u>per se</u> <class-ref scheme="cpc">H02G11/02</class-ref>; arrangements for storing and repeatedly paying-out and re-storing lengths of conductors or cables <class-ref scheme="cpc">B65H75/34</class-ref>; extensible conductors or cables, e.g. self-coiling cords <class-ref scheme="cpc">H01B7/06</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/1041" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/1041</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Mechanical or electronic switches, or control elements </text><reference><text>switches in general <class-ref scheme="cpc">H01H</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/105" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/105</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Earpiece supports, e.g. ear hooks </text><reference><text>for stereophonic headphones <class-ref scheme="cpc">H04R5/0335</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/1058" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/1058</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Manufacture or assembly</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/1066" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/1066</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Constructional aspects of the interconnection between earpiece and earpiece support </text><reference><text>earpiece support for monophonic headphones <class-ref scheme="cpc">H04R1/105</class-ref>; earpiece support for stereophonic headphones <class-ref scheme="cpc">H04R5/0335</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/1075" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/1075</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Mountings of transducers in earphones or headphones</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/1083" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/1083</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Reduction of ambient noise </text><reference><text>active noise reduction <u>per se</u> <class-ref scheme="cpc">G10K11/175</class-ref>; protective devices for the ear, e.g. providing acoustic protection <class-ref scheme="cpc">A61F11/06</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/1091" definition-exists="true" ipc-concordant="H04R1/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2016-05-01" status="published"><classification-symbol>H04R1/1091</classification-symbol><class-title date-revised="2016-05-01"><title-part><CPC-specific-text><text>Details not provided for in groups <class-ref scheme="cpc">H04R1/1008</class-ref>&#160;-&#160;<class-ref scheme="cpc">H04R1/1083</class-ref></text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/12" definition-exists="true" ipc-concordant="H04R1/12" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/12</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Sanitary or hygienic devices for mouthpieces or earpieces, e.g. for protecting against infection</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/14" definition-exists="true" ipc-concordant="H04R1/14" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/14</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Throat mountings for microphones</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/16" definition-exists="false" ipc-concordant="H04R1/16" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/16</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Mounting or connecting stylus to transducer with or without damping means</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/18" definition-exists="false" ipc-concordant="H04R1/18" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/18</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Holders for styli</text></title-part><title-part><text>Mounting holders on transducers</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/20" definition-exists="true" ipc-concordant="H04R1/20" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/20</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Arrangements for obtaining desired frequency or directional characteristics </text><reference><text>for stereophonic purpose <class-ref scheme="cpc">H04R5/00</class-ref></text></reference></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/22" definition-exists="true" ipc-concordant="H04R1/22" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/22</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>for obtaining desired frequency characteristic only </text><reference><text>circuit for combining transducers having different responses <class-ref scheme="cpc">H04R3/00</class-ref> </text><CPC-specific-text><text>for hearing aids <class-ref scheme="cpc">H04R25/407</class-ref></text></CPC-specific-text></reference></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/222" definition-exists="false" ipc-concordant="H04R1/22" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/222</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for microphones </text><reference><text><class-ref scheme="cpc">H04R1/24</class-ref>, <class-ref scheme="cpc">H04R1/26</class-ref> take precedence</text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/225" definition-exists="false" ipc-concordant="H04R1/22" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/225</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for telephonic receivers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/227" definition-exists="false" ipc-concordant="H04R1/22" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/227</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using transducers reproducing the same frequency band</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/24" definition-exists="false" ipc-concordant="H04R1/24" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/24</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Structural combinations of separate transducers or of two parts of the same transducer and responsive respectively to two or more frequency ranges</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/245" definition-exists="false" ipc-concordant="H04R1/24" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/245</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>of microphones</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/26" definition-exists="false" ipc-concordant="H04R1/26" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/26</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Spatial arrangements of separate transducers responsive to two or more frequency ranges</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/265" definition-exists="false" ipc-concordant="H04R1/26" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/265</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>of microphones</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/28" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/28</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducer mountings or enclosures modified by provision of mechanical or acoustic impedances, e.g. resonator, damping means </text><CPC-specific-text><reference><text>combinations of transducers with horns, i.e. front-loaded horns <class-ref scheme="cpc">H04R1/30</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/2803" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2803</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/2807" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2807</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Enclosures comprising vibrating or resonating arrangements </text><reference><text>for the reduction of undesired resonances or vibrations <class-ref scheme="cpc">H04R1/2869</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/2811" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2811</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/2815" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2815</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>of the bass reflex type</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/2819" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2819</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/2823" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2823</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Vents, i.e. ports, e.g. shape thereof or tuning thereof with damping material </text><reference><text>number or position of ports <class-ref scheme="cpc">H04R1/2815</class-ref>; vents in bandpass type enclosures <class-ref scheme="cpc">H04R1/2846</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="14" additional-only="false" sort-key="H04R1/2826" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2826</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/283" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/283</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using a passive diaphragm</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/2834" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2834</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/2838" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2838</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>of the bandpass type</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/2842" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2842</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/2846" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2846</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Vents, i.e. ports, e.g. shape thereof or tuning thereof with damping material </text><reference><text>number or position of ports <class-ref scheme="cpc">H04R1/2838</class-ref>; vents in bass reflex type enclosures <class-ref scheme="cpc">H04R1/2823</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="14" additional-only="false" sort-key="H04R1/2849" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2849</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/2853" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2853</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using an acoustic labyrinth or a transmission line</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/2857" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2857</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/2861" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2861</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using a back-loaded horn</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/2865" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2865</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/2869" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2869</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Reduction of undesired resonances, i.e. standing waves within enclosure, or of undesired vibrations, i.e. of the enclosure itself</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/2873" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2873</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/2876" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2876</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>by means of damping material, e.g. as cladding </text><reference><text>damping material for tuning desired resonances <class-ref scheme="cpc">H04R1/2807</class-ref>, e.g. in vents <class-ref scheme="cpc">H04R1/2823</class-ref>, <class-ref scheme="cpc">H04R1/2846</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/288" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/288</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/2884" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2884</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>by means of the enclosure structure, i.e. strengthening or shape of the enclosure </text><reference><text>by means of Helmholtz resonators <class-ref scheme="cpc">H04R1/2869</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/2888" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2888</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/2892" definition-exists="true" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2892</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Mountings or supports for transducers</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="13" additional-only="false" sort-key="H04R1/2896" definition-exists="false" ipc-concordant="H04R1/28" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/2896</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeaker transducers</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/30" definition-exists="true" ipc-concordant="H04R1/30" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/30</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Combinations of transducers with horns, e.g. with mechanical matching means </text><CPC-specific-text><text>, i.e. front-loaded horns</text></CPC-specific-text><reference><text>horns in general <class-ref scheme="cpc">G10K</class-ref>; </text><CPC-specific-text><text>transducer enclosures or mountings using a back-loaded horn <class-ref scheme="cpc">H04R1/2861</class-ref>; application of horns as guiding means to obtain a predetermined directivity characteristic <class-ref scheme="cpc">H04R1/345</class-ref></text></CPC-specific-text></reference></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R1/32" definition-exists="true" ipc-concordant="H04R1/32" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/32</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>for obtaining desired directional characteristic only </text><CPC-specific-text><reference><text>specially adapted for hearing aids <class-ref scheme="cpc">H04R25/40</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/323" definition-exists="false" ipc-concordant="H04R1/32" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/323</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeakers </text><reference><text><class-ref scheme="cpc">H04R1/34</class-ref> and <class-ref scheme="cpc">H04R1/40</class-ref> take precedence</text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/326" definition-exists="false" ipc-concordant="H04R1/32" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/326</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for microphones </text><reference><text><class-ref scheme="cpc">H04R1/34</class-ref> and <class-ref scheme="cpc">H04R1/40</class-ref> take precedence</text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/34" definition-exists="true" ipc-concordant="H04R1/34" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/34</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>by using a single transducer with sound reflecting, diffracting, directing or guiding means </text><CPC-specific-text><reference><text>specially adapted for hearing aids <class-ref scheme="cpc">H04R25/402</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/342" definition-exists="false" ipc-concordant="H04R1/34" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/342</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for microphones</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/345" definition-exists="true" ipc-concordant="H04R1/34" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/345</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeakers</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R1/347" definition-exists="true" ipc-concordant="H04R1/34" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/347</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for obtaining a phase-shift between the front and back acoustic wave</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/36" definition-exists="true" ipc-concordant="H04R1/36" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/36</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>by using a single aperture of dimensions not greater than the shortest operating wavelength</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/38" definition-exists="false" ipc-concordant="H04R1/38" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/38</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>in which sound waves act upon both sides of a diaphragm and incorporating acoustic phase-shifting means, e.g. pressure-gradient microphone</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R1/40" definition-exists="true" ipc-concordant="H04R1/40" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/40</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>by combining a number of identical transducers </text><CPC-specific-text><reference><text>specially adapted for hearing aids <class-ref scheme="cpc">H04R25/405</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/403" definition-exists="true" ipc-concordant="H04R1/40" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/403</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>loud-speakers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R1/406" definition-exists="true" ipc-concordant="H04R1/40" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/406</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>microphones</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/42" definition-exists="false" ipc-concordant="H04R1/42" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/42</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Combinations of transducers with fluid-pressure or other non-electrical amplifying means</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/44" definition-exists="false" ipc-concordant="H04R1/44" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/44</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Special adaptations for subaqueous use, e.g. for hydrophone</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R1/46" definition-exists="true" ipc-concordant="H04R1/46" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R1/46</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Special adaptations for use as contact microphones, e.g. on musical instrument, on stethoscope </text><reference><text>throat mountings <class-ref scheme="cpc">H04R1/14</class-ref></text></reference></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R3/00" definition-exists="true" ipc-concordant="H04R3/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Circuits for transducers </text><CPC-specific-text><text>, loudspeakers or microphones</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R3/002" definition-exists="false" ipc-concordant="H04R3/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/002</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Damping circuit arrangements for transducers, e.g. motional feedback circuits</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R3/005" definition-exists="true" ipc-concordant="H04R3/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/005</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for combining the signals of two or more microphones </text><reference><text>specially adapted for hearing aids <class-ref scheme="cpc">H04R25/407</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R3/007" definition-exists="false" ipc-concordant="H04R3/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/007</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Protection circuits for transducers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R3/02" definition-exists="true" ipc-concordant="H04R3/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>for preventing acoustic reaction </text><CPC-specific-text><text>, i.e. acoustic oscillatory feedback </text><reference><text>specially adapted for hearing aids <class-ref scheme="cpc">H04R25/453</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R3/04" definition-exists="true" ipc-concordant="H04R3/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>for correcting frequency response</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R3/06" definition-exists="false" ipc-concordant="H04R3/06" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/06</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>of electrostatic transducers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R3/08" definition-exists="false" ipc-concordant="H04R3/08" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/08</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>of electromagnetic transducers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R3/10" definition-exists="false" ipc-concordant="H04R3/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/10</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>of variable resistance microphones</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R3/12" definition-exists="true" ipc-concordant="H04R3/12" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/12</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>for distributing signals to two or more loudspeakers </text><CPC-specific-text><reference><text>specially adapted for hearing aids <class-ref scheme="cpc">H04R25/407</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R3/14" definition-exists="false" ipc-concordant="H04R3/14" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R3/14</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Cross-over networks</text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R5/00" definition-exists="true" ipc-concordant="H04R5/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R5/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Stereophonic arrangements </text><reference><text>stereophonic pick-ups <class-ref scheme="cpc">H04R9/16</class-ref>, <class-ref scheme="cpc">H04R11/12</class-ref>, <class-ref scheme="cpc">H04R17/08</class-ref>, <class-ref scheme="cpc">H04R19/10</class-ref></text></reference></title-part></class-title><notes-and-warnings date-revised="2013-01-01"><note type="note"><note-paragraph>In this group, the expression &quot;stereophonic arrangements&quot; covers quadraphonic or similar arrangements.</note-paragraph></note></notes-and-warnings>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R5/02" definition-exists="true" ipc-concordant="H04R5/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R5/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Spatial or constructional arrangements of loudspeakers</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R5/023" definition-exists="false" ipc-concordant="H04R5/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R5/023</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>in a chair, pillow</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R5/027" definition-exists="true" ipc-concordant="H04R5/027" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R5/027</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Spatial or constructional arrangements of microphones, e.g. in dummy heads</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R5/033" definition-exists="true" ipc-concordant="H04R5/033" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R5/033</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Headphones for stereophonic communication </text><CPC-specific-text><reference><text>details thereof, e.g. relating to batteries, cables or control elements <class-ref scheme="cpc">H04R1/10</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R5/0335" definition-exists="true" ipc-concordant="H04R5/033" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R5/0335</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Earpiece support, e.g. headbands or neckrests </text><reference><text>for monophonic headphones <class-ref scheme="cpc">H04R1/105</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R5/04" definition-exists="true" ipc-concordant="H04R5/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R5/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Circuit arrangements, </text><CPC-specific-text><text>e.g. for selective connection of amplifier inputs/outputs to loudspeakers, for loudspeaker detection, or for adaptation of settings to personal preferences or hearing impairments </text><reference><text>combinations of amplifiers <class-ref scheme="cpc">H03F3/68</class-ref>; stereophonic systems <class-ref scheme="cpc">H04S</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R7/00" definition-exists="true" ipc-concordant="H04R7/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Diaphragms for electromechanical transducers </text><reference><text>in general <class-ref scheme="cpc">F16J3/00</class-ref></text></reference></title-part><title-part><text>Cones </text><reference><text>for musical instruments <class-ref scheme="cpc">G10</class-ref> </text></reference><CPC-specific-text><reference><text>cones, diaphragms or the like, for emitting or receiving sound in general <class-ref scheme="cpc">G10K13/00</class-ref>; Mounting thereof</text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R7/02" definition-exists="true" ipc-concordant="H04R7/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>characterised by the construction</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R7/04" definition-exists="true" ipc-concordant="H04R7/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Plane diaphragms</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R7/045" definition-exists="true" ipc-concordant="H04R7/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/045</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using the distributed mode principle, i.e. whereby the acoustic radiation is emanated from uniformly distributed free bending wave vibration induced in a stiff panel and not from pistonic motion</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R7/06" definition-exists="false" ipc-concordant="H04R7/06" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/06</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>comprising a plurality of sections or layers</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R7/08" definition-exists="false" ipc-concordant="H04R7/08" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/08</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>comprising superposed layers separated by air or other fluid</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R7/10" definition-exists="false" ipc-concordant="H04R7/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/10</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>comprising superposed layers in contact</text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R7/12" definition-exists="false" ipc-concordant="H04R7/12" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/12</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Non-planar diaphragms or cones</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R7/122" definition-exists="false" ipc-concordant="H04R7/12" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/122</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>comprising a plurality of sections or layers</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R7/125" definition-exists="false" ipc-concordant="H04R7/12" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/125</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>comprising a plurality of superposed layers in contact</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R7/127" definition-exists="true" ipc-concordant="H04R7/12" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/127</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>dome-shaped</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R7/14" definition-exists="true" ipc-concordant="H04R7/14" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/14</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>corrugated, pleated or ribbed</text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R7/16" definition-exists="true" ipc-concordant="H04R7/16" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/16</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Mounting or tensioning of diaphragms or cones</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R7/18" definition-exists="true" ipc-concordant="H04R7/18" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/18</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>at the periphery</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R7/20" definition-exists="true" ipc-concordant="H04R7/20" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/20</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Securing diaphragm or cone resiliently to support by flexible material, springs, cords, or strands</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R7/22" definition-exists="true" ipc-concordant="H04R7/22" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/22</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Clamping rim of diaphragm or cone against seating</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R7/24" definition-exists="true" ipc-concordant="H04R7/24" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/24</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Tensioning by means acting directly on free portions of diaphragm or cone</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R7/26" definition-exists="true" ipc-concordant="H04R7/26" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R7/26</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Damping by means acting directly on free portion of diaphragm or cone </text><reference><text>air damping <class-ref scheme="cpc">H04R1/28</class-ref></text></reference></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R9/00" definition-exists="true" ipc-concordant="H04R9/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers of moving-coil, moving-strip, or moving-wire type</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R9/02" definition-exists="true" ipc-concordant="H04R9/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R9/022" definition-exists="false" ipc-concordant="H04R9/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/022</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Cooling arrangements</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R9/025" definition-exists="true" ipc-concordant="H04R9/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/025</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Magnetic circuit</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R9/027" definition-exists="true" ipc-concordant="H04R9/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/027</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Air gaps using a magnetic fluid</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R9/04" definition-exists="true" ipc-concordant="H04R9/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Construction, mounting, or centering of coil</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R9/041" definition-exists="false" ipc-concordant="H04R9/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/041</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Centering</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R9/042" definition-exists="false" ipc-concordant="H04R9/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/042</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>by pressurised air</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R9/043" definition-exists="true" ipc-concordant="H04R9/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/043</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Inner suspension or damper, e.g. spider </text><reference><text>outer suspension or surround <class-ref scheme="cpc">H04R7/16</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R9/045" definition-exists="true" ipc-concordant="H04R9/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/045</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Mounting </text><reference><text><class-ref scheme="cpc">H04R9/043</class-ref> takes precedence</text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R9/046" definition-exists="true" ipc-concordant="H04R9/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/046</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Construction</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="11" additional-only="false" sort-key="H04R9/047" definition-exists="false" ipc-concordant="H04R9/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/047</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>in which the windings of the moving coil lay in the same plane</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="12" additional-only="false" sort-key="H04R9/048" definition-exists="false" ipc-concordant="H04R9/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/048</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>of the ribbon type</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R9/06" definition-exists="true" ipc-concordant="H04R9/06" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/06</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Loudspeakers</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R9/063" definition-exists="false" ipc-concordant="H04R9/06" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/063</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using a plurality of acoustic drivers </text><reference><text><class-ref scheme="cpc">H04R1/24</class-ref> and <class-ref scheme="cpc">H04R1/403</class-ref> take precedence</text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R9/066" definition-exists="true" ipc-concordant="H04R9/06" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/066</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using the principle of inertia</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R9/08" definition-exists="true" ipc-concordant="H04R9/08" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/08</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Microphones</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R9/10" definition-exists="true" ipc-concordant="H04R9/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/10</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Telephone receivers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R9/12" definition-exists="false" ipc-concordant="H04R9/12" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/12</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Gramophone pick-ups using a stylus</text></title-part><title-part><text>Recorders using a stylus</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R9/14" definition-exists="false" ipc-concordant="H04R9/14" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/14</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>comprising two or more styli or transducers </text><reference><text><class-ref scheme="cpc">H04R9/16</class-ref> takes precedence</text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R9/16" definition-exists="false" ipc-concordant="H04R9/16" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/16</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>signals recorded or played back by vibration of a stylus in two orthogonal directions simultaneously</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R9/18" definition-exists="false" ipc-concordant="H04R9/18" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R9/18</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Resonant transducers, i.e. adapted to produce maximum output at a predetermined frequency</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R11/00" definition-exists="true" ipc-concordant="H04R11/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R11/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers of moving-armature or moving-core type </text><reference><text>acoustic diaphragm of magnetisable material directly coacting with electromagnet <class-ref scheme="cpc">H04R13/00</class-ref></text></reference></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R11/02" definition-exists="true" ipc-concordant="H04R11/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R11/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Loudspeakers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R11/04" definition-exists="false" ipc-concordant="H04R11/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R11/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Microphones</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R11/06" definition-exists="true" ipc-concordant="H04R11/06" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R11/06</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Telephone receivers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R11/08" definition-exists="false" ipc-concordant="H04R11/08" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R11/08</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Gramophone pick-ups using a stylus</text></title-part><title-part><text>Recorders using a stylus</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R11/10" definition-exists="false" ipc-concordant="H04R11/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R11/10</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>comprising two or more styli or transducers </text><reference><text><class-ref scheme="cpc">H04R11/12</class-ref> takes precedence</text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R11/12" definition-exists="false" ipc-concordant="H04R11/12" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R11/12</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>signals being recorded or played back by vibration of a stylus in two orthogonal directions simultaneously</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R11/14" definition-exists="false" ipc-concordant="H04R11/14" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R11/14</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Resonant transducers, i.e. adapted to produce maximum output at a predetermined frequency</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R13/00" definition-exists="true" ipc-concordant="H04R13/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R13/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers having an acoustic diaphragm of magnetisable material directly co-acting with electromagnet</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R13/02" definition-exists="false" ipc-concordant="H04R13/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R13/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Telephone receivers</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R15/00" definition-exists="true" ipc-concordant="H04R15/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2023-02-01" status="published"><classification-symbol>H04R15/00</classification-symbol><class-title date-revised="2023-02-01"><title-part><text>Magnetostrictive transducers </text><reference><text>magnetostrictive elements in general <class-ref scheme="cpc">H10N30/00</class-ref></text></reference></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R15/02" definition-exists="false" ipc-concordant="H04R15/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R15/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Resonant transducers, i.e. adapted to produce maximum output at a predetermined frequency</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R17/00" definition-exists="true" ipc-concordant="H04R17/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2023-02-01" status="published"><classification-symbol>H04R17/00</classification-symbol><class-title date-revised="2023-02-01"><title-part><text>Piezo-electric transducers</text></title-part><title-part><text>Electrostrictive transducers </text><reference><text>piezo-electric or electrostrictive elements in general <class-ref scheme="cpc">H10N30/00</class-ref>; details of piezo-electric or electrostrictive motors, generators or positioners </text><CPC-specific-text><text><class-ref scheme="cpc">H10N30/00</class-ref></text></CPC-specific-text></reference></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R17/005" definition-exists="true" ipc-concordant="H04R17/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R17/005</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using a piezo-electric polymer</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R17/02" definition-exists="true" ipc-concordant="H04R17/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R17/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Microphones</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R17/025" definition-exists="true" ipc-concordant="H04R17/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R17/025</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using a piezo-electric polymer</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R17/04" definition-exists="false" ipc-concordant="H04R17/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R17/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Gramophone pick-ups using a stylus</text></title-part><title-part><text>Recorders using a stylus</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R17/06" definition-exists="false" ipc-concordant="H04R17/06" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R17/06</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>comprising two or more styli or transducers </text><reference><text><class-ref scheme="cpc">H04R17/08</class-ref> takes precedence</text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R17/08" definition-exists="false" ipc-concordant="H04R17/08" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R17/08</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>signals being recorded or played back by vibration of a stylus in two orthogonal directions simultaneously</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R17/10" definition-exists="false" ipc-concordant="H04R17/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R17/10</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Resonant transducers, i.e. adapted to produce maximum output at a predetermined frequency</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R19/00" definition-exists="true" ipc-concordant="H04R19/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Electrostatic transducers</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R19/005" definition-exists="true" ipc-concordant="H04R19/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/005</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using semiconductor materials</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R19/01" definition-exists="false" ipc-concordant="H04R19/01" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/01</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>characterised by the use of electrets</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R19/013" definition-exists="false" ipc-concordant="H04R19/01" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/013</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeakers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R19/016" definition-exists="false" ipc-concordant="H04R19/01" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/016</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for microphones</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R19/02" definition-exists="true" ipc-concordant="H04R19/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Loudspeakers </text><reference><text><class-ref scheme="cpc">H04R19/01</class-ref> takes precedence</text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R19/04" definition-exists="true" ipc-concordant="H04R19/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Microphones </text><reference><text><class-ref scheme="cpc">H04R19/01</class-ref> takes precedence</text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R19/06" definition-exists="false" ipc-concordant="H04R19/06" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/06</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Gramophone pick-ups using a stylus</text></title-part><title-part><text>Recorders using a stylus </text><reference><text><class-ref scheme="cpc">H04R19/01</class-ref> takes precedence</text></reference></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R19/08" definition-exists="false" ipc-concordant="H04R19/08" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/08</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>comprising two or more styli or transducers </text><reference><text><class-ref scheme="cpc">H04R19/10</class-ref> takes precedence</text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R19/10" definition-exists="false" ipc-concordant="H04R19/10" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R19/10</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>signals being recorded or played back by vibration of a stylus in two orthogonal directions simultaneously</text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R21/00" definition-exists="true" ipc-concordant="H04R21/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R21/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Variable-resistance transducers </text><reference><text>gaseous resistance transducers <class-ref scheme="cpc">H04R23/00</class-ref>; magneto-resistive transducers <class-ref scheme="cpc">H04R23/00</class-ref></text></reference></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R21/02" definition-exists="false" ipc-concordant="H04R21/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R21/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Microphones</text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R21/021" definition-exists="false" ipc-concordant="H04R21/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R21/021</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>with granular resistance material</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R21/023" definition-exists="false" ipc-concordant="H04R21/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R21/023</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>with more than one granular chamber</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R21/025" definition-exists="false" ipc-concordant="H04R21/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R21/025</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>disposition of the granular chamber in microphones</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R21/026" definition-exists="false" ipc-concordant="H04R21/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R21/026</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>in which the sound is perpendicular to the current crossing the transducer material</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R21/028" definition-exists="false" ipc-concordant="H04R21/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R21/028</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>with a fluid as resistance material</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R21/04" definition-exists="false" ipc-concordant="H04R21/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R21/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Gramophone pick-ups using a stylus</text></title-part><title-part><text>Recorders using a stylus</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R23/00" definition-exists="true" ipc-concordant="H04R23/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2016-05-01" status="published"><classification-symbol>H04R23/00</classification-symbol><class-title date-revised="2016-05-01"><title-part><text>Transducers other than those covered by groups <class-ref scheme="cpc">H04R9/00</class-ref>&#160;-&#160;<class-ref scheme="cpc">H04R21/00</class-ref> </text><CPC-specific-text><reference><text>diaphragms for transducers of the distributed-mode type <class-ref scheme="cpc">H04R7/045</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R23/002" definition-exists="false" ipc-concordant="H04R23/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R23/002</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using electrothermic-effect transducer</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R23/004" definition-exists="true" ipc-concordant="H04R23/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R23/004</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using ionised gas</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R23/006" definition-exists="true" ipc-concordant="H04R23/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R23/006</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using solid state devices </text><reference><text>solid state devices <u>per se</u> <class-ref scheme="cpc">H01L</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R23/008" definition-exists="false" ipc-concordant="H04R23/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R23/008</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using optical signals for detecting or generating sound</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R23/02" definition-exists="false" ipc-concordant="H04R23/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R23/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers using more than one principle simultaneously</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R25/00" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/00</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Deaf-aid sets </text><CPC-specific-text><text>, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception </text><reference><text>electrical stimulation of auditory nerves to promote the auditory function <class-ref scheme="cpc">A61N1/36038</class-ref>; optical stimulation of auditory nerves to promote the auditory function <class-ref scheme="cpc">A61N5/0622</class-ref></text></reference></CPC-specific-text></title-part></class-title><notes-and-warnings date-revised="2013-01-01"><note type="note"><note-paragraph> Classification should be directed to groups <class-ref scheme="cpc">H04R25/02</class-ref>, <class-ref scheme="cpc">H04R25/04</class-ref> or <class-ref scheme="cpc">H04R25/50</class-ref> and its subgroups, if and only if the technical subject in consideration cannot be classified elsewhere under the main group <class-ref scheme="cpc">H04R25/00</class-ref></note-paragraph></note></notes-and-warnings>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/02" definition-exists="false" ipc-concordant="H04R25/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>adapted to be supported entirely by ear</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/04" definition-exists="true" ipc-concordant="H04R25/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>comprising pocket amplifiers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/30" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/30</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>Monitoring or testing of hearing aids, e.g. functioning, settings, battery power</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/305" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/305</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Self-monitoring or self-testing</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/35" definition-exists="false" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/35</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using translation techniques</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/353" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/353</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Frequency, e.g. frequency shift or compression</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/356" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/356</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Amplitude, e.g. amplitude shift or compression</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/40" definition-exists="false" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/40</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Arrangements for obtaining a desired directivity characteristic</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/402" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/402</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using contructional means</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/405" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/405</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>by combining a plurality of transducers</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/407" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/407</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Circuits for combining signals of a plurality of transducers</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/43" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-01-01" status="published"><classification-symbol>H04R25/43</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Electronic input selection or mixing based on input signal analysis, e.g. mixing or selection between microphone and telecoil or between microphones with different directivity characteristics </text><reference><text><class-ref scheme="cpc">H04R25/407</class-ref> takes precedence</text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/45" definition-exists="false" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/45</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Prevention of acoustic reaction, i.e. acoustic oscillatory feedback</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/453" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/453</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>electronically</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/456" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/456</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>mechanically</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/48" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/48</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>using constructional means for obtaining a desired frequency response </text><reference><text><class-ref scheme="cpc">H04R25/652</class-ref> takes precedence</text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/50" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/50</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Customised settings for obtaining desired overall acoustical characteristics</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/502" definition-exists="false" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/502</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using analog signal processing</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/505" definition-exists="false" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/505</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using digital signal processing</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R25/507" definition-exists="false" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/507</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>implemented by neural network or fuzzy logic</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/55" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/55</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>using an external connection, either wireless or wired</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/552" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/552</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Binaural</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/554" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/554</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>using a wireless connection, e.g. between microphone and amplifier or using Tcoils</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/556" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R25/556</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>External connectors, e.g. plugs or modules </text><reference><text><class-ref scheme="cpc">H04R25/607</class-ref> takes precedence</text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/558" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/558</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>Remote control, e.g. of amplification, frequency</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/60" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R25/60</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>Mounting or interconnection of hearing aid parts, e.g. inside tips, housings or to ossicles </text><reference><text>ear wax retarders, e.g. mounting thereof <class-ref scheme="cpc">H04R25/654</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/602" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/602</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>of batteries</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/603" definition-exists="false" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R25/603</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>of mechanical or electronic switches or control elements</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/604" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/604</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>of acoustic or vibrational transducers</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R25/606" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/606</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>acting directly on the eardrum, the ossicles or the skull, e.g. mastoid, tooth, maxillary or mandibular bone, or mechanically stimulating the cochlea, e.g. at the oval window</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/607" definition-exists="false" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R25/607</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>of earhooks</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/609" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R25/609</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>of circuitry </text><reference><text>of electronic switches or control elements <class-ref scheme="cpc">H04R25/603</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/65" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/65</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Housing parts, e.g. shells, tips or moulds, or their manufacture</text></CPC-specific-text></title-part></class-title><notes-and-warnings><note type="note"><note-paragraph>Housing parts for mechanical mounting or interconnection of hearing aid parts covered by <class-ref scheme="cpc">H04R25/60</class-ref> are to be classified in <class-ref scheme="cpc">H04R25/60</class-ref> </note-paragraph></note></notes-and-warnings>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/652" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R25/652</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>Ear tips; Ear moulds </text><reference><text>hybrid ear moulds or post-processing thereof for their customisation <class-ref scheme="cpc">H04R25/659</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R25/654" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/654</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Ear wax retarders</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R25/656" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-01-01" status="published"><classification-symbol>H04R25/656</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Non-customized, universal ear tips, i.e. ear tips which are not specifically adapted to the size or shape of the ear or ear canal</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R25/658" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-01-01" status="published"><classification-symbol>H04R25/658</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Manufacture of housing parts</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R25/659" definition-exists="false" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R25/659</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>Post-processing of hybrid ear moulds for customisation, e.g. in-situ curing</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/70" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R25/70</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Adaptation of deaf aid to hearing loss, e.g. initial electronic fitting</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R25/75" definition-exists="true" ipc-concordant="H04R25/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R25/75</classification-symbol><class-title date-revised="2019-05-01"><title-part><CPC-specific-text><text>Electric tinnitus maskers providing an auditory perception</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R27/00" definition-exists="true" ipc-concordant="H04R27/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R27/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Public address systems </text><reference><text>circuits for preventing acoustic reaction <class-ref scheme="cpc">H04R3/02</class-ref>; circuits for distributing signals to loudspeakers <class-ref scheme="cpc">H04R3/12</class-ref>; </text><CPC-specific-text><text>monitoring or testing arrangements for public address systems <class-ref scheme="cpc">H04R29/007</class-ref></text></CPC-specific-text><text>; amplifiers <class-ref scheme="cpc">H03F</class-ref></text></reference></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R27/02" definition-exists="true" ipc-concordant="H04R27/02" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R27/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Amplifying systems for the deaf</text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R27/04" definition-exists="false" ipc-concordant="H04R27/04" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R27/04</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Electric megaphones</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R29/00" definition-exists="true" ipc-concordant="H04R29/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R29/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Monitoring arrangements</text></title-part><title-part><text>Testing arrangements </text><CPC-specific-text><reference><text>for hearing aids <class-ref scheme="cpc">H04R25/30</class-ref>; detection of loudspeaker connection <class-ref scheme="cpc">H04R5/04</class-ref>; sound-field adaptation dependent on speaker detection <class-ref scheme="cpc">H04S7/308</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R29/001" definition-exists="true" ipc-concordant="H04R29/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R29/001</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for loudspeakers </text><reference><text><class-ref scheme="cpc">H04R29/007</class-ref> takes precedence</text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R29/002" definition-exists="true" ipc-concordant="H04R29/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R29/002</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Loudspeaker arrays</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R29/003" definition-exists="true" ipc-concordant="H04R29/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R29/003</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>of the moving-coil type</text></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R29/004" definition-exists="true" ipc-concordant="H04R29/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R29/004</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for microphones </text><reference><text><class-ref scheme="cpc">H04R29/007</class-ref> takes precedence</text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="9" additional-only="false" sort-key="H04R29/005" definition-exists="true" ipc-concordant="H04R29/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R29/005</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Microphone arrays</text></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="10" additional-only="false" sort-key="H04R29/006" definition-exists="true" ipc-concordant="H04R29/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R29/006</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Microphone matching</text></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R29/007" definition-exists="true" ipc-concordant="H04R29/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R29/007</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for public address systems </text><reference><text>public address systems <u>per se</u> <class-ref scheme="cpc">H04R27/00</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R29/008" definition-exists="true" ipc-concordant="H04R29/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R29/008</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Visual indication of individual signal levels </text><reference><text>visual indication of stereophonic sound image <class-ref scheme="cpc">H04S7/40</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="7" additional-only="false" sort-key="H04R31/00" definition-exists="true" ipc-concordant="H04R31/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R31/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor </text><CPC-specific-text><reference><text>manufacture of microstructural arrangements of deformable or non-deformable structures in general <class-ref scheme="cpc">B81C1/00182</class-ref></text></reference></CPC-specific-text></title-part></class-title>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R31/003" definition-exists="true" ipc-concordant="H04R31/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R31/003</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>for diaphragms or their outer suspension</text></CPC-specific-text></title-part></class-title></classification-item>
<classification-item breakdown-code="false" not-allocatable="false" level="8" additional-only="false" sort-key="H04R31/006" definition-exists="true" ipc-concordant="H04R31/00" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R31/006</classification-symbol><class-title date-revised="2013-01-01"><title-part><CPC-specific-text><text>Interconnection of transducer parts </text><reference><text>of diaphragm and outer suspension by moulding <class-ref scheme="cpc">H04R31/003</class-ref></text></reference></CPC-specific-text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="true" level="6" additional-only="true" sort-key="H04R201/00" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/00</classification-symbol>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R201/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R2201/00</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Details of transducers, loudspeakers or microphones covered by <class-ref scheme="cpc">H04R1/00</class-ref> but not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R201/003" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/003</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Mems transducers or their use </text><reference><text>of the electrostatic type <class-ref scheme="cpc">H04R19/005</class-ref></text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R201/02" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/02</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details casings, cabinets or mounting therein for transducers covered by <class-ref scheme="cpc">H04R1/02</class-ref> but not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/021" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/021</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers or their casings adapted for mounting in or to a wall or ceiling</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/023" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/023</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers incorporated in garment, rucksacks or the like</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/025" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/025</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducer mountings or cabinet supports enabling variable orientation of transducer of cabinet</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/028" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/028</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Structural combinations of loudspeakers with built-in power amplifiers, e.g. in the same acoustic enclosure </text><reference><text><class-ref scheme="cpc">H04R2499/10</class-ref> takes precedence; Single (sub)woofer with two or more satellite loudspeakers for mid- and high-frequency band reproduction driven via the (sub)woofer <class-ref scheme="cpc">H04R2205/026</class-ref></text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/029" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/029</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Manufacturing aspects of enclosures transducers</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R201/10" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/10</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details of earpieces, attachments therefor, earphones or monophonic headphones covered by <class-ref scheme="cpc">H04R1/10</class-ref> but not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/103" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/103</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Combination of monophonic or stereophonic headphones with audio players, e.g. integrated in the headphone</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/105" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/105</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Manufacture of mono- or stereophonic headphone components</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/107" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/107</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Monophonic and stereophonic headphones with microphone for two-way hands free communication</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/109" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/109</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Arrangements to adapt hands free headphones for use on both ears</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R201/34" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/34</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Directing or guiding sound by means of a phase plug</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R201/40" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/40</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details of arrangements for obtaining desired directional characteristic by combining a number of identical transducers covered by <class-ref scheme="cpc">H04R1/40</class-ref> but not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/401" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/401</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>2D or 3D arrays of transducers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/403" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/403</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Linear arrays of transducers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R201/405" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2201/405</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Non-uniform arrays of transducers or a plurality of uniform arrays with different transducer spacing</text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R203/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R2203/00</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Details of circuits for transducers, loudspeakers or microphones covered by <class-ref scheme="cpc">H04R3/00</class-ref> but not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R203/12" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2203/12</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Beamforming aspects for stereophonic sound reproduction with loudspeaker arrays</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R205/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R2205/00</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Details of stereophonic arrangements covered by <class-ref scheme="cpc">H04R5/00</class-ref> but not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R205/021" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2205/021</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects relating to docking-station type assemblies to obtain an acoustical effect, e.g. the type of connection to external loudspeakers or housings, frequency improvement</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R205/022" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2205/022</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Plurality of transducers corresponding to a plurality of sound channels in each earpiece of headphones or in a single enclosure</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R205/024" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2205/024</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Positioning of loudspeaker enclosures for spatial sound reproduction</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R205/026" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2205/026</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Single (sub)woofer with two or more satellite loudspeakers for mid- and high-frequency band reproduction driven via the (sub)woofer</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R205/041" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2205/041</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Adaptation of stereophonic signal reproduction for the hearing impaired</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R207/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R2207/00</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Details of diaphragms or cones for electromechanical transducers or their suspension covered by <class-ref scheme="cpc">H04R7/00</class-ref> but not provided for in <class-ref scheme="cpc">H04R7/00</class-ref> or in <class-ref scheme="cpc">H04R2307/00</class-ref></text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R207/021" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2207/021</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Diaphragm extensions, not necessarily integrally formed, e.g. skirts, rims, flanges</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R209/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R2209/00</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Details of transducers of the moving-coil, moving-strip, or moving-wire type covered by <class-ref scheme="cpc">H04R9/00</class-ref> but not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R209/021" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2209/021</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Reduction of eddy currents in the magnetic circuit of electrodynamic loudspeaker transducer</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R209/022" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2209/022</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects regarding the stray flux internal or external to the magnetic circuit, e.g. shielding, shape of magnetic circuit, flux compensation coils</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R209/024" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2209/024</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Manufacturing aspects of the magnetic circuit of loudspeaker or microphone transducers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R209/026" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2209/026</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers having separately controllable opposing diaphragms, e.g. for ring-tone and voice </text><reference><text><class-ref scheme="cpc">H04R2400/03</class-ref> takes precedence</text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R209/027" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2209/027</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Electrical or mechanical reduction of yoke vibration</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R209/041" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2209/041</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Voice coil arrangements comprising more than one voice coil unit on the same bobbin</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R209/043" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2209/043</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Short circuited voice coils driven by induction</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R217/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R2217/00</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Details of magnetostrictive, piezo-electric, or electrostrictive transducers covered by <class-ref scheme="cpc">H04R15/00</class-ref> or <class-ref scheme="cpc">H04R17/00</class-ref> but not provided for in any of their subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R217/01" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2217/01</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Non-planar magnetostrictive, piezo-electric or electrostrictive benders</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R217/03" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2217/03</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Parametric transducers where sound is generated or captured by the acoustic demodulation of amplitude modulated ultrasonic waves</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R225/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details of deaf aids covered by <class-ref scheme="cpc">H04R25/00</class-ref>, not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/021" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R2225/021</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Behind the ear [BTE] hearing aids</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R225/0213" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R2225/0213</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Constructional details of earhooks, e.g. shape, material</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R225/0216" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R2225/0216</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>BTE hearing aids having a receiver in the ear mould</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/023" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/023</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Completely in the canal [CIC] hearing aids</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/025" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/025</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>In the ear hearing aids [ITE] hearing aids</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/31" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/31</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects of the use of accumulators in hearing aids, e.g. rechargeable batteries or fuel cells</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/33" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/33</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects relating to adaptation of the battery voltage, e.g. its regulation, increase or decrease</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/39" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/39</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects relating to automatic logging of sound environment parameters and the performance of the hearing aid during use, e.g. histogram logging, or of user selected programs or settings in the hearing aid, e.g. usage logging</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/41" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/41</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Detection or adaptation of hearing aid parameters or programs to listening situation, e.g. pub, forest</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/43" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/43</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Signal processing in hearing aids to enhance the speech intelligibility</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/49" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2016-08-01" status="published"><classification-symbol>H04R2225/49</classification-symbol><class-title date-revised="2016-08-01"><title-part><text>Reducing the effects of electromagnetic noise on the functioning of hearing aids, by, e.g. shielding, signal processing adaptation, selective (de)activation of electronic parts in hearing aid</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/51" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2019-05-01" status="published"><classification-symbol>H04R2225/51</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Aspects of antennas or their circuitry in or for hearing aids</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/53" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/53</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Hearing aid for unilateral hearing impairment using Contralateral Routing Of Signals [CROS]</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/55" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/55</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Communication between hearing aids and external devices via a network for data exchange</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/57" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R2225/57</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Aspects of electrical interconnection between hearing aid parts</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/59" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/59</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Arrangements for selective connection between one or more amplifiers and one or more receivers within one hearing aid</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/61" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2022-01-01" status="published"><classification-symbol>H04R2225/61</classification-symbol><class-title date-revised="2019-05-01"><title-part><text>Aspects relating to mechanical or electronic switches or control elements, e.g. functioning</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/67" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/67</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Implantable hearing aids or parts thereof not covered by <class-ref scheme="cpc">H04R25/606</class-ref></text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/77" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/77</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Design aspects, e.g. CAD, of hearing aid tips, moulds or housings</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/81" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/81</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects of electrical fitting of hearing aids related to problems arising from the emotional state of a hearing aid user, e.g. nervousness or unwillingness during fitting</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R225/83" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2225/83</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects of electrical fitting of hearing aids related to problems arising from growth of the hearing aid user, e.g. children</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R227/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2227/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details of public address [PA] systems covered by <class-ref scheme="cpc">H04R27/00</class-ref> but not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R227/001" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2227/001</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Adaptation of signal processing in PA systems in dependence of presence of noise</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R227/003" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2016-08-01" status="published"><classification-symbol>H04R2227/003</classification-symbol><class-title date-revised="2016-08-01"><title-part><text>Digital PA systems using, e.g. LAN or internet</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R227/005" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2227/005</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Audio distribution systems for home, i.e. multi-room use</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R227/007" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2227/007</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Electronic adaptation of audio signals to reverberation of the listening space for PA</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R227/009" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2227/009</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Signal processing in [PA] systems to enhance the speech intelligibility</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R231/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2231/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details of apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor covered by <class-ref scheme="cpc">H04R31/00</class-ref>, not provided for in its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R231/001" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2231/001</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Moulding aspects of diaphragm or surround</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R231/003" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2231/003</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Manufacturing aspects of the outer suspension of loudspeaker or microphone diaphragms or of their connecting aspects to said diaphragms</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R307/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2307/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details of diaphragms or cones for electromechanical transducers, their suspension or their manufacture covered by <class-ref scheme="cpc">H04R7/00</class-ref> or <class-ref scheme="cpc">H04R31/003</class-ref>, not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R307/021" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2307/021</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Diaphragms comprising cellulose-like materials, e.g. wood, paper, linen</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R307/023" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2307/023</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Diaphragms comprising ceramic-like materials, e.g. pure ceramic, glass, boride, nitride, carbide, mica and carbon materials</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R307/025" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2307/025</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Diaphragms comprising polymeric materials</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R307/027" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2307/027</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Diaphragms comprising metallic materials</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R307/029" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2307/029</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Diaphragms comprising fibres</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R307/201" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2307/201</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Damping aspects of the outer suspension of loudspeaker diaphragms by addition of additional damping means</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R307/204" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2307/204</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Material aspects of the outer suspension of loudspeaker diaphragms</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R307/207" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2307/207</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Shape aspects of the outer suspension of loudspeaker diaphragms</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R400/00" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2400/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Loudspeakers</text></title-part></class-title><notes-and-warnings date-revised="2013-01-01"><note type="note"><note-paragraph><class-ref scheme="cpc">H04R2400/00</class-ref> itself is only to be used for those cases where the classification does not allow specification the type of transducer and the type is important, e.g. frequency control circuit ( <class-ref scheme="cpc">H04R3/04</class-ref> and subgroups) may require different circuits for microphones or for loudspeakers </note-paragraph></note></notes-and-warnings>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R400/01" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2400/01</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers used as a loudspeaker to generate sound aswell as a microphone to detect sound</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R400/03" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2016-08-01" status="published"><classification-symbol>H04R2400/03</classification-symbol><class-title date-revised="2016-08-01"><title-part><text>Transducers capable of generating both sound as well as tactile vibration, e.g. as used in cellular phones</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R400/07" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2400/07</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Suspension between moving magnetic core and housing</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R400/11" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2400/11</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects regarding the frame of loudspeaker transducers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R400/13" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2400/13</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Use or details of compression drivers</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R410/00" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2410/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Microphones</text></title-part></class-title><notes-and-warnings date-revised="2013-01-01"><note type="note"><note-paragraph><class-ref scheme="cpc">H04R2410/00</class-ref> itself is only to be used for those cases where the classification does not allow specification the type of transducer and the type is important, e.g. frequency control circuit ( <class-ref scheme="cpc">H04R3/04</class-ref> and subgroups) may require different circuits for microphones or for loudspeakers </note-paragraph></note></notes-and-warnings>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R410/01" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2410/01</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Noise reduction using microphones having different directional characteristics</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R410/03" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2410/03</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Reduction of intrinsic noise in microphones</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R410/05" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2410/05</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Noise reduction with a separate noise microphone</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R410/07" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2410/07</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Mechanical or electrical reduction of wind noise generated by wind passing a microphone</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R420/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2420/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details of connection covered by <class-ref scheme="cpc">H04R</class-ref>, not provided for in its groups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R420/01" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2420/01</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Input selection or mixing for amplifiers or loudspeakers </text><reference><text>for hearing aids <class-ref scheme="cpc">H04R25/43</class-ref></text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R420/03" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2420/03</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Connection circuits to selectively connect loudspeakers or headphones to amplifiers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R420/05" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2420/05</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Detection of connection of loudspeakers or headphones to amplifiers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R420/07" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2420/07</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Applications of wireless loudspeakers or wireless microphones</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R420/09" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2420/09</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Applications of special connectors, e.g. USB, XLR, in loudspeakers, microphones or headphones</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R430/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2430/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Signal processing covered by <class-ref scheme="cpc">H04R</class-ref>, not provided for in its groups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R430/01" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2430/01</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects of volume control, not necessarily automatic, in sound systems</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R430/03" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2430/03</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Synergistic effects of band splitting and sub-band processing</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R430/20" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2430/20</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Processing of the output signals of the acoustic transducers of an array for obtaining a desired directivity characteristic </text><reference><text><class-ref scheme="cpc">H04R2203/12</class-ref> takes precedence</text></reference></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R430/21" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2430/21</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Direction finding using differential microphone array [DMA]</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R430/23" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2430/23</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Direction finding using a sum-delay beam-former</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R430/25" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2430/25</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Array processing for suppression of unwanted side-lobes in directivity characteristics, e.g. a blocking matrix</text></title-part></class-title></classification-item></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R440/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2440/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Bending wave transducers covered by <class-ref scheme="cpc">H04R</class-ref>, not provided for in its groups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R440/01" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2440/01</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Acoustic transducers using travelling bending waves to generate or detect sound</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R440/03" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2440/03</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Resonant bending wave transducer used as a microphone</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R440/05" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2440/05</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects relating to the positioning and way or means of mounting of exciters to resonant bending wave panels</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R440/07" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2440/07</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Loudspeakers using bending wave resonance and pistonic motion to generate sound</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R460/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Details of hearing devices, i.e. of ear- or headphones covered by <class-ref scheme="cpc">H04R1/10</class-ref> or <class-ref scheme="cpc">H04R5/033</class-ref> but not provided for in any of their subgroups, or of hearing aids covered by <class-ref scheme="cpc">H04R25/00</class-ref> but not provided for in any of its subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R460/01" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/01</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Hearing devices using active noise cancellation</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R460/03" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/03</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects of the reduction of energy consumption in hearing devices</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R460/05" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/05</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Electronic compensation of the occlusion effect</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R460/07" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/07</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Use of position data from wide-area or local-area positioning systems in hearing devices, e.g. program or information selection</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R460/09" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/09</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Non-occlusive ear tips, i.e. leaving the ear canal open, for both custom and non-custom tips </text><reference><text><class-ref scheme="cpc">H04R2460/11</class-ref> takes precedence</text></reference></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R460/11" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/11</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects relating to vents, e.g. shape, orientation, acoustic properties in ear tips of hearing devices to prevent occlusion</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R460/13" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/13</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Hearing devices using bone conduction transducers</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R460/15" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/15</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Determination of the acoustic seal of ear moulds or ear tips of hearing devices</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R460/17" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2460/17</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Hearing device specific tools used for storing or handling hearing devices or parts thereof, e.g. placement in the ear, replacement of cerumen barriers, repair, cleaning hearing devices</text></title-part></class-title></classification-item></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="7" additional-only="true" sort-key="H04R499/00" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2015-07-01" status="published"><classification-symbol>H04R2499/00</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Aspects covered by <class-ref scheme="cpc">H04R</class-ref> or <class-ref scheme="cpc">H04S</class-ref> not otherwise provided for in their subgroups</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R499/01" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2499/01</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>General technical reviews, overviews, tutorials</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="8" additional-only="true" sort-key="H04R499/10" definition-exists="false" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2499/10</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>General applications</text></title-part></class-title>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R499/11" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2499/11</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA&apos;s, camera&apos;s</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R499/13" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2499/13</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Acoustic transducers and sound field adaptation in vehicles</text></title-part></class-title></classification-item>
<classification-item breakdown-code="true" not-allocatable="false" level="9" additional-only="true" sort-key="H04R499/15" definition-exists="true" ipc-concordant="CPCONLY" c-set-base-allowed="false" c-set-subsequent-allowed="true" date-revised="2013-01-01" status="published"><classification-symbol>H04R2499/15</classification-symbol><class-title date-revised="2013-01-01"><title-part><text>Transducers incorporated in visual displaying devices, e.g. televisions, computer displays, laptops</text></title-part></class-title></classification-item></classification-item></classification-item></classification-item></classification-item></class-scheme>