IEC 61606-4:2005

INTERNATIONAL IEC
STANDARD 61606-4
First edition
2005-12
Audio and audiovisual equipment –
Digital audio parts – Basic measurement
methods of audio characteristics –
Part 4:
Personal computer
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INTERNATIONAL IEC
STANDARD 61606-4
First edition
2005-12
Audio and audiovisual equipment –
Digital audio parts – Basic measurement
methods of audio characteristics –
Part 4:
Personal computer
 IEC 2005  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, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
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International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 61606-4  IEC:2005(E)
CONTENTS
FOREWORD.4

1 Scope.6
2 Normative references .6
3 Terms, definitions and abbreviated terms .6
3.1 Terms and definitions .6
3.2 Abbreviated terms .8
3.3 Rated values .8
4 Measuring conditions.8
4.1 Environmental conditions .8
4.2 Power supplies.8
4.3 Test signal frequencies .9
4.4 Standard setting .10
4.5 Working setting .11
4.6 Preconditioning .12
5 Measuring instruments .12
5.1 Analogue signal generator.12
5.2 Analogue in-band level meter .12
5.3 Analogue low-pass filter .12
5.4 Analogue weighting filter .12
5.5 Standard medium .12
5.6 Recording medium .13
5.7 Software for digital data evaluation.13
5.8 Short-term distortion meter.14
5.9 Other instruments.14
6 Methods of measurement (digital-in/analogue-out) .14
6.1 Input/output characteristics .15
6.2 Frequency response.16
6.3 Noise characteristics .17
6.4 Distortion characteristics .21
7 Methods of measurement (analogue-in/digital-out) .23
7.1 Input/output characteristics .23
7.2 Frequency response.25
7.3 Noise characteristics .26
7.4 Distortion characteristics .29

Figure 1 – Block diagram for maximum output amplitude measurement .15
Figure 2 – Block diagram for gain difference between channels measurement .16
Figure 3 – Block diagram for frequency-response measurement .16
Figure 4 – Block diagram for signal-to-noise ratio measurement .17
Figure 5 – Block diagram for dynamic range measurement .18
Figure 6 – Block diagram for channel separation measurement.20
Figure 7 – Block diagram for distortion and noise measurement.21
Figure 8 – Block diagram for short-term distortion measurement.22
Figure 9 – Block diagram for maximum allowable input amplitude measurement .23

61606-4  IEC:2005(E) – 3 –
Figure 10 – Block diagram for gain difference between channel and tracking error
measurement.24
Figure 11 – Block diagram for frequency response measurement.25
Figure 12 – Block diagram for signal-to-noise ratio measurement .26
Figure 13 – Block diagram for dynamic range measurement .27
Figure 14 – Block diagram for channel separation measurement.28
Figure 15 – Block diagram for distortion and noise measurement.29
Figure 16 – Block diagram for short-term distortion measurement.30

Table 1 – Frequencies used in the measurement .9

– 4 – 61606-4  IEC:2005(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
AUDIO AND AUDIOVISUAL EQUIPMENT –
DIGITAL AUDIO PARTS –
BASIC MEASUREMENT METHODS
OF AUDIO CHARACTERISTICS –
Part 4: Personal computer
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61606-4 has been prepared by IEC technical committee 100:
Audio, video and multimedia equipment and systems.
The text of this standard is based on the following documents:
CDV Report on voting
100/952/CDV 100/1030/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

61606-4  IEC:2005(E) – 5 –
IEC 61606 consists of the following parts under the general title Audio and audiovisual
equipment – Digital audio parts – Basic measurement methods of audio characteristics:
Part 1: General
Part 2: Consumer use
Part 3: Professional use
Part 4: Personal computer
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.
———————
Under consideration.
– 6 – 61606-4  IEC:2005(E)
AUDIO AND AUDIOVISUAL EQUIPMENT –
DIGITAL AUDIO PARTS –
BASIC MEASUREMENT METHODS
OF AUDIO CHARACTERISTICS –
Part 4: Personal computer
1 Scope
This part of IEC 61606 specifies the basic measurement methods of a linear PCM signal for
an audio part of personal computers (PCs) and applies to both desktop and portable
computers. The common measuring conditions and methods are described in IEC 61606-1.
Specific conditions and methods of measurement for PCs are given in this standard.
NOTE 1 The methods described are mostly based on sampling frequencies from 8 kHz to 192 kHz and bit length
from 8 bit to 24 bit.
NOTE 2 This standard describes tests for equipment which has digital input with analogue output and analogue
input with digital output. Digital input data are provided from an internal HDD or other
...