IEC 60268-3:2000

Sound system equipment - Part 3: Amplifiers

Applies to analogue amplifiers and the analogue parts of digital/analogue amplifiers that form part of a sound system for professional or household applications. Specifies the characteristics to be included in specifications of amplifiers and the corresponding methods of measurement.

Equipements pour systèmes électroacoustiques - Partie 3: Amplificateurs

S'applique aux amplificateurs analogiques et aux parties analogiques des amplificateurs analogiques/numériques, qui font partie d'un système électroacoustique destiné à des applications professionnelles ou grand public. Spécifie les caractèristiques qu'il convient d'inclure dans les spécifications des amplificateurs, ainsi que les méthodes de mesure correspondante.

General Information

• Status: Published
• Publication Date: 29-Aug-2000
• ICS: 33.160.10 - Amplifiers
• Technical Committee: TC 100 - Audio, video and multimedia systems and equipment
• Drafting Committee: MT 60268-3 - TC 100/MT 60268-3
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 23-Apr-2013

Relations

• Revised: IEC 60268-3:2013 - Sound system equipment - Part 3: Amplifiers
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD
60268-3
Third edition
2000-08
Sound system equipment –
Part 3:
Amplifiers
Equipements pour systèmes électroacoustiques –
Partie 3:
Amplificateurs
Reference number
Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.
Consolidated editions
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edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the
base publication incorporating amendment 1 and the base publication incorporating
amendments 1 and 2.
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INTERNATIONAL IEC
STANDARD
60268-3
Third edition
2000-08
Sound system equipment –
Part 3:
Amplifiers
Equipements pour systèmes électroacoustiques –
Partie 3:
Amplificateurs
 IEC 2000  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: [phone] e-mail: [e-mail] IEC web site http://www.iec.ch
Commission Electrotechnique Internationale
PRICE CODE
XA
International Electrotechnical Commission
For price, see current catalogue

– 2 – 60268-3 © IEC:2000(E)
CONTENTS
Page
FOREWORD . 5
Clause
1 Scope . 7
2 Normative references. 7
3 Conditions. 8
3.1 Rated conditions and standard measuring conditions. 8
3.1.1 Introduction. 8
3.1.2 Rated conditions . 8
3.1.3 Standard measuring conditions . 9
3.2 Other conditions . 9
4 Classes of operation . 9
5 Interchangeable parts . 10
6 Automatic controls . 10
7 Power supply . 10
8 Position of the volume controls . 10
9 Pre-conditioning for measurements. 10
10 Series of measurements . 11
11 Variable consumption apparatus . 11
12 Marking. 11
13 Operating environment. 12
14 Characteristics to be specified, and their methods of measurement . 12
14.1 Power supply characteristics. 12
14.1.1 Characteristics to be specified . 12
14.1.2 Method of measurement. 12
14.2 Tolerance of (long-term) power supply voltage variations. 12
14.2.1 Characteristic to be specified . 12
14.2.2 Methods of measurement. 13
14.3 Tolerance of power supply frequency variations. 14
14.3.1 Characteristics to be specified . 14
14.3.2 Methods of measurement. 14
14.4 Tolerance of power supply harmonics and ripple. 14
14.4.1 Characteristics to be specified . 14
14.4.2 Methods of measurement. 15
14.5 Input characteristics. 15
14.5.1 Rated source impedance, characteristic to be specified . 15
14.5.2 Input impedance . 15
14.5.3 Rated source e.m.f., characteristic to be specified . 17
14.5.4 Minimum source e.m.f. for rated distortion-limited output voltage . 17
14.6 Output characteristics . 17
14.6.1 Rated load impedance, characteristic to be specified . 17
14.6.2 Output source impedance . 18
14.6.3 Output voltage and power (distortion-limited) . 18

60268-3 © IEC:2000(E) – 3 –
Clause Page
14.6.4 Regulation . 20
14.6.5 Overload restoring time. 20
14.7 Limiting characteristics . 20
14.7.1 Overload source e.m.f. 20
14.7.2 Short-term maximum output voltage and power. 21
14.7.3 Long-term maximum output voltage and power . 22
14.7.4 Temperature-limited output power. 23
14.8 Characteristics of protection circuits . 23
14.8.1 Introduction. 23
14.8.2 Protection against potentially damaging combinations of output voltage
and current . 24
14.8.3 Characteristics of d.c. offset protection circuits . 25
14.9 Sustaining-time for rated (distortion-limited) output voltage or power . 26
14.9.1 Introduction. 26
14.9.2 Characteristic to be specified . 27
14.9.3 Method of measurement. 27
14.10 Gain. 28
14.10.1 Voltage gain and e.m.f. gain . 28
14.10.2 Maximum e.m.f. gain. 28
14.10.3 Attenuation characteristic of the volume control . 28
14.10.4 Attenuation characteristic of balance controls for
multi-channel equipment. 29
14.11 Response. 29
14.11.1 Gain-frequency response. 29
14.11.2 Gain-limited effective frequency range . 30
14.11.3 Distortion-limited effective frequency range . 30
14.11.4 Phase-frequency response . 30
14.12 Amplitude non-linearity. 31
14.12.1 Introduction . 31
14.12.2 Rated total harmonic distortion . 31
14.12.3 Total harmonic distortion under standard measuring conditions . 31
14.12.4 Total harmonic distortion as a function of amplitude and frequency. 32
14.12.5 Harmonic distortion of the nth order under standard
measuring conditions . 32
14.12.6 Harmonic distortion of the nth order as a function of amplitude
and frequency. 33
14.12.7 Modulation distortion of the nth order. 34
14.12.8 Difference-frequency distortion of the nth order . 35
14.12.9 Dynamic intermodulation distortion (DIM). 37
14.12.10 Total difference frequency distortion . 38
14.12.11 Weighted total harmonic distortion . 40
14.13 Noise . 40
14.13.1 Characteristic to be specified. 40
14.13.2 Method of measurement . 41
14.14 Hum . 41
14.14.1 Introduction . 41
14.14.2 Characteristics to be specified . 41
14.14.3 Method of measurement . 42

– 4 – 60268-3 © IEC:2000(E)
Clause Page
14.15 Balanced inputs and outputs . 42
14.15.1 Balance of the input. 42
14.15.2 Overload (distortion-limited) peak-to-peak common-mode input voltage. 43
14.15.3 Balance of the output. 44
14.16 Cross-talk and separation in multi-channel amplifiers. 45
14.16.1 Characteristics to be specified . 45
14.16.2 Method of measurement . 45
14.17 Gain and phase differences between channels in multi-channel amplifiers . 46
14.17.1 Gain difference . 46
14.17.2 Phase difference. 47
14.18 Dimensions and mass, characteristics to be specified . 47
Annex A (informative) Balanced interfaces . 53
Bibliography . 54
Figure 1 – Arrangements for measuring input impedance . 48
Figure 2 – Oscillogram when measuring overload restoring time . 49
Figure 3 – Protection against potentially damaging combinations of output voltage
and current. 50
Figure 4 – Arrangement for combining two input signals. 51
Figure 5 – Frequency spectrum below 30 kHz of the signal fo
...

IEC 60268-3
Edition 3.0 2000-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Sound system equipment –
Part 3: Amplifiers
Equipements pour systèmes électroacoustiques –
Partie 3: Amplificateurs
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by
any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or
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IEC 60268-3
Edition 3.0 2000-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Sound system equipment –
Part 3: Amplifiers
Equipements pour systèmes électroacoustiques –
Partie 3: Amplificateurs
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XA
CODE PRIX
ICS 33.160.10 ISBN 2-8318-5567-5
– 2 – 60268-3 © CEI:2000
SOMMAIRE
Pages
AVANT-PROPOS.8
Articles
1 Domaine d’application.12
2 Références normatives.12
3 Conditions.14
3.1 Conditions nominales et conditions normales de mesure.14
3.1.1 Introduction.14
3.1.2 Conditions nominales.16
3.1.3 Conditions normales de mesure .16
3.2 Autres conditions.16
4 Classes de fonctionnement.18
5 Eléments interchangeables.18
6 Commandes automatiques.18
7 Alimentation.18
8 Position des commandes de gain .20
9 Préconditionnement pour les mesures .20
10 Série de mesures .20
11 Appareils à consommation variable .20
12 Marquage.22
13 Environnement d’utilisation.22
14 Caractéristiques à spécifier et méthodes de mesure correspondantes .22
14.1 Caractéristiques de l’alimentation .22
14.1.1 Caractéristiques à spécifier .22
14.1.2 Méthode de mesure.24
14.2 Tolérance sur les variations (à long terme) de la tension d’alimentation.24
14.2.1 Caractéristiques à spécifier .24
14.2.2 Méthodes de mesure.26
14.3 Tolérance sur les variations de la tension d’alimentation .26
14.3.1 Caractéristiques à spécifier .26
14.3.2 Méthodes de mesure.28
14.4 Tolérance sur les harmoniques et l’ondulation de l’alimentation.28
14.4.1 Caractéristiques à spécifier .28
14.4.2 Méthodes de mesure.28
14.5 Caractéristiques d’entrée.30
14.5.1 Impédance nominale de source, caractéristiques à spécifier.30
14.5.2 Impédance d’entrée.30
14.5.3 F.é.m. nominale de source, caractéristique à spécifier.32
14.5.4 F.é.m. minimale de source pour la tension nominale de sortie
limitée par la distorsion.34
14.6 Caractéristiques de sortie.34
14.6.1 Impédance nominale de charge, caractéristique à spécifier .34
14.6.2 Impédance de sortie.36
14.6.3 Tension et puissance de sortie (limitée par la distorsion) .36
14.6.4 Régulation.38
14.6.5 Temps de récupération après surcharge .40

60268-3 © IEC:2000 – 3 –
CONTENTS
Page
FOREWORD.9
Clause
1 Scope.13
2 Normative references.13
3 Conditions.15
3.1 Rated conditions and standard measuring conditions.15
3.1.1 Introduction.15
3.1.2 Rated conditions.17
3.1.3 Standard measuring conditions .17
3.2 Other conditions.17
4 Classes of operation.19
5 Interchangeable parts.19
6 Automatic controls.19
7 Power supply.19
8 Position of the volume controls.21
9 Pre-conditioning for measurements .21
10 Series of measurements .21
11 Variable consumption apparatus.21
12 Marking.23
13 Operating environment .23
14 Characteristics to be specified, and their methods of measurement.23
14.1 Power supply characteristics.23
14.1.1 Characteristics to be specified .23
14.1.2 Method of measurement.25
14.2 Tolerance of (long-term) power supply voltage variations .25
14.2.1 Characteristic to be specified .25
14.2.2 Methods of measurement.27
14.3 Tolerance of power supply frequency variations.27
14.3.1 Characteristics to be specified .27
14.3.2 Methods of measurement.29
14.4 Tolerance of power supply harmonics and ripple .29
14.4.1 Characteristics to be specified .29
14.4.2 Methods of measurement.29
14.5 Input characteristics.31
14.5.1 Rated source impedance, characteristic to be specified .31
14.5.2 Input impedance .31
14.5.3 Rated source e.m.f., characteristic to be specified .33
14.5.4 Minimum source e.m.f. for rated distortion-limited output voltage .35
14.6 Output characteristics.35
14.6.1 Rated load impedance, characteristic to be specified .35
14.6.2 Output source impedance .37
14.6.3 Output voltage and power (distortion-limited) .37
14.6.4 Regulation.
...