Sound system equipment - Part 7: Headphones and earphones

Applies to headphones and headsets intended to be used on the human ear. Standardizes the designation and description of headphones, and lists characteristics to be specified, with the relevant methods of measurement.

Elektroakustische Geräte - Teil 7: Kopfhörer und Ohrhörer

Equipements pour systèmes électroacoustiques - Partie 7: Casques et écouteurs

S'applique aux casques et casques microphoniques prévus pour être utilisés sur l'oreille humaine. Normalise la désignation et la description des écouteurs et énumère les caractéristiques à spécifier, ainsi que les méthodes de mesure correspondantes qui les concernent.

Sound system equipment -- Part 7: Headphones and earphones (IEC 60268-7:1996)

General Information

Status
Withdrawn
Publication Date
12-May-1996
Withdrawal Date
30-Nov-1996
Current Stage
9960 - Withdrawal effective - Withdrawal
Start Date
02-Jan-2014
Completion Date
02-Jan-2014

Relations

Buy Standard

Standard
EN 60268-7:1999
English language
37 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)


SLOVENSKI STANDARD
01-april-1999
Sound system equipment -- Part 7: Headphones and earphones (IEC 60268-7:1996)
Sound system equipment -- Part 7: Headphones and earphones
Elektroakustische Geräte -- Teil 7: Kopfhörer und Ohrhörer
Equipements pour systèmes électroacoustiques -- Partie 7: Casques et écouteurs
Ta slovenski standard je istoveten z: EN 60268-7:1996
ICS:
33.160.50 Pribor Accessories
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEI
NORME
IEC
INTERNATIONALE
268-7
INTERNATIONAL
Deuxième édition
STANDARD Second edition
1996-02
systèmes électroacoustiques -
Equipements pour
Partie 7:
Casques et écouteurs
-
Sound system equipment
Part 7:
Headphones and earphones
O CEI 1996 Droits de reproduction réservés — Copyright — all rights reserved
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 pro- any form or by any means, electronic or mechanical,
cédé, électronique ou mécanique, y compris la photocopie et including photocopying and microfilm, without permission
les microfilms, sans l'accord écrit de l'éditeur. in writing from the publisher.
Genève, Suisse
Bureau Central de la Commission Electrotechnique Internationale 3, rue de Varembé
Commission Electrotechnique Internationale CODE PRIX
I EC
International Electrotechnical Commission
PRICE CODE
MetHnyHapoAHae 3neKTporeXHH4ecitaa IHOMHCCHH
voir catalogue en vigueur
Pour prix, •
For price, see current catalogue

268-7 © IEC:1996 - 3 -
CONTENTS
Page
FOREWORD
Clause
1 General 7
1.1 Scope 7
1.2 Normative references
1.3 Definitions
13 1.4 Classification, designation and coding
Marking of terminals, controls and polarity
1.5
21 1.6 User instructions
21 Conditions for specifications and measurements
Rated conditions 2.1
23 2.2 Standard conditions for measurement
2.3 Couplers and ear simulators
2.4 Loudness comparison conditions
27 2.5 Ear canal sound pressure level measurement conditions
27 3 Characteristics to be specified and their methods of measurement
3.1 Power supply
27 3.2 Electrical impedance
3.3 Input voltage 29
35 3.4 Input power
35 3.5 Sound pressure (level)
37 3.6 Frequency response
45 3.7 Amplitude non-linearity
49 Rated climatic conditions (these are rated conditions)
3.8
51 3.9 External magnetic field
51 3.10 Unwanted sound radiation
3.11 Sound attenuation
3.12 Crosstalk attenuation for multi-channel headphones
3.13 Application force (this is a rated condition)
53 3.14 Physical characteristics, cables and connectors
4 Classification of characteristics
Annexes
A Specification and conditions of use of a microphone for use inside the ear canal
Practical details of free-field comparison conditions
B
61 Practical details of diffuse-field comparison conditions
C
Practical details of the subjective comparison and ear canal sound pressure level
D
conditions
Bibliography E
268-7 © IEC:1996 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
SOUND SYSTEM EQUIPMENT -
Part 7: Headphones and earphones
FOREWORD
The IEC (International Electrotechnical Commission) is a worldwide organization for standardization
1)
comprising all national electrotechnical committees (IEC National Committees). The object of the IEC is to
promote international cooperation on all questions concerning standardization in the electrical and
electronic fields. To this end and in addition to other activities, the IEC publishes International Standards.
Their preparation is entrusted to technical committees; any IEC National Committee interested in
the subject dealt with may participate in this preparatory work. International, governmental and
non-governmental organizations liaising with the IEC also participate in this preparation. The IEC
collaborates closely with the International Organization for Standardization (ISO) in accordance with
conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of the IEC on technical matters, express as nearly as possible an
international consensus of opinion on the relevant subjects since each technical committee has
representation from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the
form of standards, technical reports or guides and they are accepted by the National Committees in that
sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the
subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 268-7 has been prepared by IEC technical committee 84:
Equipment and systems in the field of audio, video and audiovisual engineering.
This second edition cancels and replaces the first edition published in 1984, and consti-
tutes a technical revision.
The text of this standard is based on the following documents:
FDIS Report on voting
84/417/FDIS 1000/4/RVD
Full information on the voting for the approval of this standard can be found in the report
on voting indicated in the above table.
Annex A forms an integral part of this standard.
Annexes B, C, D and E are for information only.

-7 -
268-7 © IEC:1996
SOUND SYSTEM EQUIPMENT -
Part 7: Headphones and earphones
1 General
1.1 Scope
This part of IEC 268 applies to headphones, headsets, earphones and earsets, intended to
be used on, or in, the human ear. It also applies to equipment, such as pre-amplifiers,
passive networks and power supplies which form an integral part of the headphone
system.
It does not deal with:
- safety, for which reference should be made to IEC 65 [1]* or another appropriate
standard;
- the characteristics of microphones of headsets, for which reference should be made
to IEC 268-4 [2];
- earphones and other devices for hearing aids, for which reference should be made
to IEC 118-0 [3];
- headphones for audiometry;
- headphones and other devices which form pa rt of an active ear-defender system,
although some of its provisions may be applicable.
This standard specifies the characteristics which should be included by the manufacturer
in specifications, and relevant methods of measurement. It includes a classification of the
different types of earphone, mainly characterized by the way in which the transducer is
coupled acoustically to the ear, and a classification code which may also be used for
marking.
1.2 Normative references
The following normative documents contain provisions which, through reference in this
text, constitute provisions of this part of IEC 268. At the time of publication, the editions
indicated were valid. All normative documents are subject to revision, and pa ies to
rt
agreements based on this pa rt of IEC 268 are encouraged to investigate the possibility of
applying the most recent editions of the normative documents indicated below. Members
of IEC and ISO maintain registers of currently valid International Standards.
IEC 38: 1983, IEC standard voltages
IEC 50(801): 1994, International Electrotechnical Vocabulary - Chapter 801: Acoustics
and electroacoustics
IEC 68: Basic environmental testing procedures
* Figures in square brackets refer to the bibliography given in annex E.

- 9 -
268-7 © IEC:1996
IEC 86: Primary batteries
Guide for specifying environmental conditions for equipment
IEC Guide 106: 1989,
performance rating
Scales and sizes for plotting frequency characteristics and polar diagrams
IEC 263: 1982,
Sound system equipment - Part 1: General
IEC 268-1: 1985,
Sound system equipment - Part 2: Explanation of general terms and
IEC 268-2: 1987,
calculation methods
Sound system equipment - Part 3: Amplifiers
IEC 268-3: 1987,
Sound system equipment - Part 11: Applications of connectors for the
IEC 268-11: 1987,
interconnection of sound system components
Sound system equipment - Part 12: Applications of connectors for
IEC 268-12: 1987,
broadcast and similar use
Sound system equipment - Part 15: Preferred matching values for the
IEC 268-15: 1987,
interconnection of sound system components
Occluded-ear simulator for the measurement of earphones coupled to the
IEC 711: 1981,
ear by ear inserts
Conference systems - Electrical and audio requirements
IEC 914: 1988,
Provisional head and torso simulator for acoustic measurements on air
IEC 959: 1990,
conduction hearing aids
Acoustics - Determination of sound power levels of noise sources -
ISO 3741: 1988,
Precision methods for broad-band sources in reverberation rooms
Acoustics - Hearing protectors - Part 1: Subjective method for the
ISO 4869-1: 1990,
measurement of sound attenuation
Acoustics - Hearing protectors - Part 3: Simplified method for the
TR 4869-3: 1989,
ISO
measurement of insertion loss of ear-muff type protectors for quality inspection purposes

268-7 ©IEC:1996 - 11 -
Definitions
1.3
of IEC 268, the following definitions apply:
rt
For the purpose of this pa
NOTE — Any device included between a transducer as defined in 1.3.1 to 1.3.15 and the connector(s) for
electrical input should be regarded as part of the transducer.
Electroacoustic transducer by which acoustic oscillations are obtained from
earphone:
1.3.1
electric signals and intended to be closely coupled acoustically to the ear. [IEV 801-27-18]
Assembly of one or two earphones on a headband or chinband, the
headphone:
1.3.2
use of which may be optional (e.g. with intra-concha earphones).
Headphones equipped with a microphone.
1.3.3 headset:
Earphones equipped with a microphone.
1.3.4 earset:
NOTE — This definition is included because the term appears in the catalogue of IEC publications.
Small earphone that is attached directly to a connecting element,
insert earphone:
1.3.5
for example an earmould, inserted into the ear canal. [IEV 801-27-22, modified]
Small earphone that fits in the concha cavity, with its
intra-concha earphone:
1.3.6
acoustic exit close to the entrance of the ear canal.
earphone" is modified from that in IEC 50(801), and the definition of "intra-
rt
NOTE — The definition of "inse
concha earphone" introduced, because the methods of measurement of the two types differ.
Earphone applied externally to the outer ear and intended
supra-aural earphone:
1.3.7
to rest on the pinna. [IEV 801-27-23, modified]
Earphone intended to rest on the ridges of the concha
1.3.8 supra-concha earphone:
cavity.
Earphone having a cavity large enough to cover the region
1.3.9 circumaural earphone:
of the head including the ear. [IEV 801-27-24]
1.3.10 ear shell: Circumaural type of earphone hanging on the ear. [IEC 914]
Insert headphone by which the earphone(s) is/are
1.3.11 stethoscopic headphone:
coupled to the ears by means of a pair of rigid tubes, so that the assembly resembles a
stethoscope.
Earphone which intentionally provides an acoustic
acoustically open earphone:
1.3.12
path between the external environment and the ear canal.
Earphone which is intended to prevent acoustic
acoustically closed earphone:
1.3.13
coupling between the external environment and the ear canal.
Earphone which does not emit significant sound radiation
1.3.14 closed-back earphone:
from the back of the transducer to the external environment.
Earphone which emits significant sound radiation from the
open-back earphone:
1.3.15
back of the transducer to the external environment.

268-7 © IEC:1996 - 13 -
1.4 Classification, designation and coding
The following designations and classification codes shall be used:
268-7 - IEC - XXXX - NNRN - N
where:
268-7-IEC is the standard form of prefix (see 2.4.7 of lEC directives, part 3, [4]);
X (first letter) gives the principle of the transducer:
-
D - electrodynamic (moving coil);
E - electret (self-polarizing);
F - piezo-electric (polymer);
M - electromagnetic (moving armature or diaphragm);
P - piezo-electric (ceramic);
S - electrostatic (externally polarized);
- X (second letter) gives the type of earphone (see figure 1):
C - circumaural;
E - intra-concha;
H - earshell;
I - inse
rt ;
M - supra-concha;
S - supra-aural;
T - stethoscopic;
X (third letter) gives the intended nature of the acoustic coupling to the ear canai:
L - acoustically open;
S - acoustically closed;
X (fourth letter) gives the intended nature of the radiation to the external
-
environment:
C - closed-back (see 1.3.13);
O - open-back (see 1.3.14);
An illustration of the four possibilities defined in 1.3.12 to 1.3.15, and indicated by the third
and fourth classification letters, is given in figure 2;
- NNRN (first number) gives the impedance in ohms in "mantissa and exponent" form.
(For example, 8 S2 as "08R0", 32 S2 as "32R0" and 600 S2 as "06R2");
- N (second number) gives the number of channels.
The code, compiled in accordance with the above rules, may be used for marking.

open earphone Ear loudspeaker
Type of earphone Acoustically closed earphone Acoustically
(minimum leakage) (controlled leakage)
HOUSING PROTECTOR PROTECTOR
PROTECTOR HOUSING HOUSING
Caudal
Caudal ; Caud al
.glii
/ } sta.
j j
Circumaural / back °/ "",/
/ / back / back
I// frontont
i/ front frontt
I
A
IIII:' Rostral Ih Rostral '''/ Rostral
EARPAD
EARPAD
TRANSDUCER
TRANSDUCER
TRANSDUCER
EARPAD
EARPAD
al
/ Cauda
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.