SIST HD 450.3 S1:2004

SLOVENSKI STANDARD
SIST HD 450.3 S1:2004
01-januar-2004
[Not translated]
Hearing aids - Part 3: Hearing aid equipment not entirely worn on the listener

Hörgeräte - Teil 3: Hörhilfen-Systeme, die nur zum Teil vom Benutzer getragen werden

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in

utilisée sous quelque forme que ce soit et par aucun any form or by any means, electronic or mechanical,

procédé, électronique ou mécanique, y compris la photo- including photocopying and microfilm, without permission in

copie et les microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.

1) The formal decisions or agreements of the IEC on technical matters, prepared by Technical Committees on which all the

National Committees having a special interest therein are represented, express, as nearly as possible, an international

2) They have the form of recommendations for international use and they are accepted by the National Committees in that

3) In order to promote international unification, the IEC expresses the wish that all National Committees should adopt the text

of the IEC recommendation for their national rules in so far as national conditions will permit. Any divergence between the

IEC recommendation and the corresponding national rules should, as far as possible, be clearly indicated in the latter.

This standard has been prepared by IEC Technical Committee No.29: Electroacoustics.

The first draft was discussed at the meeting held in Gaithersburg in 1976. As a result of this meeting, a draft, Document

29(Central Office)108, was submitted to the National Committees for approval under the Six Months' Rule in June 1977.

This second edition comprises the first edition, issued in 1979, and editorial amendments which are due to the issuing of IEC

Publications Nos. 65: Safety Requirements for Mains Operated Electronic and Related Apparatus for Household and

303: IEC Provisional Reference Coupler for the Calibration of Earphones Used in Audiometry.

318: An IEC Artificial Ear, of the Wideband Type, for the Calibration of Earphones Used in

711: Occluded-ear Simulator for the Measurement of Earphones Coupled to the Ear by Ear Inserts.

In the rehabilitation of persons having impaired hearing, use is made of two types of electroacoustic

Hearing aid equipment in which the microphone or microphones are not worn on the listener.

IEC Publication 118-0: Hearing Aids, Part 0: Measurement of Electroacoustical Characteristics, gives

details of methods of measurements on hearing aids and in general covers the requirements for other hearing

However, measurements on hearing aid equipment involve certain test differences which are detailed in

this standard. Reference is made wherever possible to IEC Publication 268: Sound System Equipment, for

The purpose of this standard is to describe a method of determining the overall electroacoustic

performance of hearing aid equipment not entirely worn on the listener, used in the rehabilitation of

The methods specified in this publication give information on the measurement of those parameters

Overall effect of transmission paths in systems where the microphone(s) is (are) not connected by

Measurements other than the above are specified in IEC publications, for example IEC Publication

Throughout this standard, all sound pressure levels specified are referred to 20 µPa. All voltage level

Note.– With non-sinusoidal signals appreciable measuring errors can arise when using instruments which measure mean

The microphone shall be placed in an acoustic test field in accordance with IEC Publication 268-4:

Part 4: Microphones, under the stated conditions appropriate to the microphone used and connected to

the amplifying system. Where the microphone is separate from the amplifier, only the microphone shall

be placed in the acoustic test field. Where the microphone is an integral part of a main unit, the whole

IEC Publication 318: An IEC Artificial Ear, of the Wideband Type, for the Calibration of

Earphones Used in Audiometry, describes the preferred device for measuring the acoustic output of

IEC Publication 303: IEC Provisional Reference Coupler for the Calibration of Earphones Used in

Audiometry, describes an acoustic coupler for supra-aural earphones which may be used if a device

Note. – Until specifications are available for an agreed method and device for measuring the performance of ci