Electroacoustics - Simulators of human head and ear - Part 7: Head and torso simulator for the measurement of sound sources close to the ear

IEC 60318-7:2022 describes a head and torso simulator, or manikin, intended for the measurement of sound sources placed close to the ear in the frequency range from 100 Hz to 16 000 Hz.
The manikin described in this document is intended for airborne acoustic measurements only. It is not suitable for measurements which depend upon vibration transmission paths such as bone conduction, or for measurements requiring the simulation of bone or tissue.
This document specifies the manikin in terms of both its geometrical dimensions and its acoustical properties. Only manikins compliant with both sets of specifications are in conformance with this document.
IEC 60318-7:2022 cancels and replaces IEC TS 60318-7:2017. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to IEC TS 60318-7:2017:
a) changing the title;
b) extending the scope to sound sources close to the ear.

Electroacoustique - Simulateurs de tête et d'oreille humaines - Partie 7: Simulateur de tête et de torse pour le mesurage des sources sonores à proximité de l'oreille

L'IEC 60318-7:2022 décrit un simulateur de tête et de torse, ou mannequin, destiné au mesurage des sources sonores placées à proximité de l'oreille dans la plage de fréquences de 100 Hz à 16 000 Hz.
Le mannequin décrit dans le présent document est destiné uniquement aux mesures acoustiques aériennes. Il n'est pas adapté aux mesures qui dépendent des voies de transmission des vibrations telles que la conduction osseuse, ni aux mesures qui exigent la simulation d'os ou de tissu.
Le présent document définit le mannequin à la fois par ses dimensions géométriques et par ses propriétés acoustiques. Seuls les mannequins conformes aux deux ensembles de spécifications sont conformes au présent document.
L'IEC 60318-7:2022 annule et remplace l'IEC TS 60318-7:2017. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'IEC TS 60318 7:2017:
a) modification du titre;
b) extension du domaine d'application aux sources sonores à proximité de l'oreille.

General Information

Status
Published
Publication Date
13-Jun-2022
Technical Committee
Current Stage
PPUB - Publication issued
Completion Date
14-Jun-2022
Ref Project

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IEC 60318-7
Edition 1.0 2022-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electroacoustics – Simulators of human head and ear –
Part 7: Head and torso simulator for the measurement of sound sources close to
the ear
Électroacoustique – Simulateurs de tête et d'oreille humaines –
Partie 7: Simulateur de tête et de torse pour le mesurage des sources sonores à
proximité de l'oreille
IEC 60318-7:2022-06(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60318-7
Edition 1.0 2022-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Electroacoustics – Simulators of human head and ear –
Part 7: Head and torso simulator for the measurement of sound sources close to
the ear
Électroacoustique – Simulateurs de tête et d'oreille humaines –
Partie 7: Simulateur de tête et de torse pour le mesurage des sources sonores à
proximité de l'oreille
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.140.50 ISBN 978-2-8322-0857-1

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 60318-7:2022 © IEC 2022
CONTENTS

FOREWORD ........................................................................................................................... 4

1 Scope .............................................................................................................................. 6

2 Normative references ...................................................................................................... 6

3 Terms and definitions ...................................................................................................... 6

4 Construction .................................................................................................................. 11

4.1 General ................................................................................................................. 11

4.2 Geometrical dimensions of the manikin ................................................................. 11

4.2.1 Head and torso .............................................................................................. 11

4.2.2 Pinna simulators for hearing aid measurements ............................................. 13

4.2.3 Ear canal extension ....................................................................................... 14

4.2.4 Ear simulator ................................................................................................. 16

4.2.5 Materials ....................................................................................................... 16

4.3 Acoustical characteristics of the manikin ............................................................... 17

4.3.1 Free-field frequency response ....................................................................... 17

4.3.2 Diffuse-field frequency response .................................................................... 19

4.3.3 Acceptance intervals ..................................................................................... 20

4.3.4 Openings ....................................................................................................... 20

5 Calibration ..................................................................................................................... 21

5.1 Reference environmental conditions ..................................................................... 21

5.2 Calibration method ................................................................................................ 21

5.2.1 General ......................................................................................................... 21

5.2.2 Test signal, test space and measurement equipment ..................................... 21

5.2.3 Measurement of sound pressure level............................................................ 22

5.2.4 Alignment of manikin azimuth and elevation .................................................. 23

5.2.5 Test for sound leakage .................................................................................. 23

6 Marking and instruction manual ..................................................................................... 23

6.1 Markings of the manikin ........................................................................................ 23

6.2 Instruction manual ................................................................................................ 24

7 Maximum permitted uncertainty of measurements ......................................................... 24

Annex A (informative) Design example of an anatomically shaped manikin .......................... 26

Annex B (informative) Design examples of a geometrically shaped manikin ......................... 27

Annex C (informative) Relationship between tolerance interval, corresponding

acceptance interval and the maximum permitted uncertainty of measurement ....................... 29

Annex D (informative) 3D representation of example pinna simulators ................................. 30

D.1 Background........................................................................................................... 30

D.2 Scanning technique .............................................................................................. 30

D.3 Examples of pinna simulator shape ....................................................................... 30

D.4 Verification of conformance ................................................................................... 31

Bibliography .......................................................................................................................... 32

Figure 1 – Manikin geometrical references .............................................................................. 8

Figure 2 – Coordinate scheme for azimuth and elevation angles ............................................. 9

Figure 3 – Illustration of manikin head and torso dimensions ................................................ 12

Figure 4 – Illustration of manikin pinna simulator dimensions ................................................ 15

Figure A.1 – Example of an anatomically shaped manikin ..................................................... 26

---------------------- Page: 4 ----------------------
IEC 60318-7:2022 © IEC 2022 – 3 –

Figure B.1 – Example 1 of a geometrically shaped manikin ................................................... 27

Figure B.2 – Example 2 of a geometrically shaped manikin ................................................... 28

Figure C.1 – Relationship between tolerance interval, corresponding acceptance

interval and the maximum permitted uncertainty of measurement ......................................... 29

Figure D.1 – Example of a pinna simulator (embedded 3D PDFs) ......................................... 31

Table 1 – Manikin head and torso dimensions ....................................................................... 13

Table 2 – Dimensions of the pinna simulator and the cylindrical ear canal extension of

the manikin ........................................................................................................................... 15

Table 3 – Dimensions of the pinna simulator and the tapered ear canal extension of

the manikin ........................................................................................................................... 16

Table 4 – Free-field frequency response of the manikin (right ear) for an azimuth angle

of 0° in one-twelfth-octave bands .......................................................................................... 18

Table 5 – Free-field frequency responses of the manikin (right ear) for azimuth angles

of 90°, 180° and 270° in one-twelfth-octave bands ................................................................ 19

Table 6 – Diffuse-field frequency response of the manikin (right ear) in one-third-

octave bands ........................................................................................................................ 20

Table 7 – Maximum permitted uncertainty U for type approval measurements ................ 25

max
---------------------- Page: 5 ----------------------
– 4 – IEC 60318-7:2022 © IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROACOUSTICS –
SIMULATORS OF HUMAN HEAD AND EAR –
Part 7: Head and torso simulator for the measurement
of sound sources close to the ear
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 international

co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and

in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,

Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). 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. 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 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 IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence between

any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and

members of its technical committees and IEC National Committees for any personal injury, property damage or

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

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.

IEC 60318-7 has been prepared by IEC technical committee 29: Electroacoustics. It is an

International Standard.

This publication contains attached files in the form of 3D PDF files. These files are intended to

be used as a complement and do not form an integral part of the publication.

This edition cancels and replaces IEC TS 60318-7:2017. This edition constitutes a technical

revision.

This edition includes the following significant technical changes with respect to

IEC TS 60318-7:2017:
a) changing the title;
b) extending the scope to sound sources close to the ear.
---------------------- Page: 6 ----------------------
IEC 60318-7:2022 © IEC 2022 – 5 –
The text of this International Standard is based on the following documents:
Draft Report on voting
29/1118/FDIS 29/1121/RVD

Full information on the voting for its approval can be found in the report on voting indicated in

the above table.
The language used for the development of this International Standard is English.

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available

at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are

described in greater detail at www.iec.ch/standardsdev/publications.

A list of all parts in the IEC 60318 series, published under the general title Electroacoustics –

Simulators of human head and ear, can be found on the IEC website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under webstore.iec.ch in the data related to the

specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates that it

contains colours which are considered to be useful for the correct understanding of its

contents. Users should therefore print this document using a colour printer.
---------------------- Page: 7 ----------------------
– 6 – IEC 60318-7:2022 © IEC 2022
ELECTROACOUSTICS –
SIMULATORS OF HUMAN HEAD AND EAR –
Part 7: Head and torso simulator for the measurement
of sound sources close to the ear
1 Scope

This part of IEC 60318 describes a head and torso simulator, or manikin, intended for the

measurement of sound sources placed close to the ear in the frequency range from 100 Hz to

16 000 Hz.

The manikin described in this document is intended for airborne acoustic measurements only.

It is not suitable for measurements which depend upon vibration transmission paths such as

bone conduction, or for measurements requiring the simulation of bone or tissue.

This document specifies the manikin in terms of both its geometrical dimensions and its

acoustical properties. Only manikins compliant with both sets of specifications are in

conformance with this document.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies.

For undated references, the latest edition of the referenced document (including any

amendments) applies.
IEC 60118-8, Electroacoustics – Hearing aids – Part 8: Methods of measurement of

performance characteristics of hearing aids under simulated in situ working conditions

IEC 60318-4, Electroacoustics – Simulators of human head and ear – Part 4: Occluded-ear

simulator for the measurement of earphones coupled to the ear by means of ear inserts

IEC 61260-1, Electroacoustics – Octave-band and fractional-octave-band filters – Part 1:

Specifications
ISO 3, Preferred numbers – Series of preferred numbers
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following

addresses:
• IEC Electropedia: available at http://www.electropedia.org
• ISO Online browsing platform: available at http://www.iso.org/obp
---------------------- Page: 8 ----------------------
IEC 60318-7:2022 © IEC 2022 – 7 –
3.1
manikin
head and torso simulator

simulator of a median adult human head and part of the torso extending in total from the top of

the head to the waist and designed to simulate the sound pick-up characteristics and acoustic

diffraction

Note 1 to entry: The head and torso simulator includes two pinna simulators, and at least one occluded-ear

simulator.
3.2
manikin type
designation of the manikin as either anatomical or geometrical in shape
3.3
pinna simulator

device which has the approximate shape and dimensions of a median adult human pinna

3.4
ear simulator

device for measuring the acoustic output of sound sources where the sound pressure is

measured by a calibrated microphone coupled to the source so that the overall acoustic

impedance of the device approximates that of the normal human ear at a given location and in

a given frequency band

Note 1 to entry: In this document, an ear simulator comprises an ear canal extension and an occluded-ear simulator

(see 4.2.4).
3.5
occluded-ear simulator

ear simulator which approximates the acoustic transfer impedance of the inner part of the ear

canal, from the tip of an ear insert to the eardrum
Note 1 to entry: An occluded-ear simulator is standardised in IEC 60318-4.
3.6
ear canal extension

device that provides a connection between the occluded-ear simulator and the aperture of the

device simulating the concha
3.7
reference plane of the occluded-ear simulator

plane perpendicular to the axis of the cavity of the simulator, chosen to pass through the

position normally occupied by the tip of an ear mould in a human ear canal
3.8
reference point of the manikin

point bisecting the line joining the right and left ear canal entrance points (EEP, 3.17)

3.9
plane of symmetry of the manikin

plane passing through the reference point of the manikin that divides the left and right portions

of the manikin into symmetrical halves, within the allowed tolerances, where left and right is

interpreted as for the human torso
Note 1 to entry: See Figure 1.
---------------------- Page: 9 ----------------------
– 8 – IEC 60318-7:2022 © IEC 2022
NOTE The reference point of the manikin is situated within the head.
Figure 1 – Manikin geometrical references
3.10
axis of rotation of the manikin

straight line about which the manikin can be rotated, passing through the reference point of the

manikin, lying in the plane of symmetry of the manikin, and having a direction that would be

vertical if the manikin were mounted in a position corresponding to that of a standing person

SEE: Figure 1.
3.11
reference plane of the manikin

plane perpendicular to the axis of rotation that contains the reference point of the manikin

SEE: Figure 1.
---------------------- Page: 10 ----------------------
IEC 60318-7:2022 © IEC 2022 – 9 –
3.12
test point

reproducible position in the test space at which the sound pressure level is measured with the

manikin absent and at which the reference point of the manikin is to be located for test purposes

Note 1 to entry: See Figure 2.
Figure 2 – Coordinate scheme for azimuth and elevation angles
3.13
test axis
line joining the test point and the acoustic centre of the sound source
SEE: Figure 2.
---------------------- Page: 11 ----------------------
– 10 – IEC 60318-7:2022 © IEC 2022
3.14
test plane
plane perpendicular to the test axis and containing the test point
3.15
azimuth angle of sound incidence

angle between the plane of symmetry of the manikin and the plane defined by the axis of rotation

of the manikin and the test axis

Note 1 to entry: When the manikin faces the sound source, the azimuth angle of sound incidence is defined as 0°.

When the right ear of the manikin faces the sound source, the angle is defined as +90°. When the left ear of the

manikin faces the sound source, the angle is defined as +270°.
SEE: Figure 2.
3.16
elevation angle of sound incidence
angle between the reference plane of the manikin and the test axis

Note 1 to entry: When the vertex points towards the sound source, the elevation angle is defined as +90°. When

the test axis lies in the reference plane of the manikin, the elevation angle is defined as 0°.

SEE: Figure 2.
3.17
ear canal entrance point
EEP

point located at the centre of the manikin ear canal at the junction between concha and ear

canal extension
3.18
transverse plane of the manikin

plane perpendicular to the plane of symmetry of the manikin and containing the axis of rotation

3.19
reference position of the manikin

position of the manikin in the test space where the reference point of the manikin coincides with

the test point, and the azimuth and elevation angles are both equal to zero
3.20
manikin free-field frequency response

difference, as a function of frequency, between the sound pressure level at the ear simulator

microphone with the reference point of the manikin at the test point within a free-field

measurement environment and the sound pressure level at the test point with the manikin

absent
3.21
manikin diffuse-field frequency response

difference, as a function of frequency, between the sound pressure level at the ear simulator

microphone with the reference point of the manikin at the test point within a diffuse-field

measurement environment and the sound pressure level at the test point with the manikin

absent
---------------------- Page: 12 ----------------------
IEC 60318-7:2022 © IEC 2022 – 11 –
4 Construction
4.1 General

The simulator consists of a head mounted on a torso that extends to the waist. The head is

equipped with simulated pinnae and one or two occluded-ear simulators formed of cavities

having acoustic impedance terminations corresponding to that of a median human adult, and

microphones located at positions corresponding to the eardrums. It has been designed to

provide acoustic diffraction similar to that encountered around the median human head and

torso. Measurement results obtained with a manikin can differ substantially from similar

measurements made on an individual person, due to anatomical variations. Measurement

results for a given hearing aid obtained with different models of manikin conforming to this

document can also differ, depending on the type and the method of fitting the hearing aid. The

same holds for measurement results obtained with the same manikin model but with different

models of pinna simulators.

NOTE 1 Above 10 kHz, an occluded-ear simulator conforming to IEC 60318‑4 does not simulate the acoustic

impedance of the human ear and can only be used as an acoustic coupler in this frequency range.

The realization of the manikin conforming to this document can be either anatomically shaped

(see Annex A) or geometrically shaped (see Annex B) and can have different anatomically

shaped pinna simulators. The realization of the ear canal entrance, together with the additional

ear canal extension, can be either cylindrical or tapered in shape. This enables measurements

of all types of insert devices, for example behind-the-ear (BTE) and in-the-ear (ITE) hearing aid

designs.

NOTE 2 Nevertheless, some specific ITE hearing aid models might not be compatible.

This document covers both the geometrical dimensions of the manikin’s head, torso, pinnae

and ear canals and the manikin’s acoustical characteristics. As a minimum, the manikin shall

be specified with cylindrical ear canal extensions and comply with the appropriate acoustical

characteristics. Optionally, tapered ear canal extensions may also be specified. The model and

type of the manikin used (see 3.2) and the model of the pinna simulator used shall be stated

when giving results of measurements made with the manikin.
4.2 Geometrical dimensions of the manikin
4.2.1 Head and torso

The geometrical dimensions of the head and the torso are illustrated in Figure 3, and listed in

Table 1. The realization of the head (excluding the pinnae) and of the torso can be either

anatomically shaped or geometrically shaped. Anatomically shaped manikins are not

necessarily completely symmetrical and may be described as "quasi-symmetrical", when

staying within the allowable differences from the completely symmetrical manikin. Both

anatomically and geometrically shaped manikins shall conform to the specified ranges of

geometrical dimensions and acoustical characteristics specified in this document.

The acceptance interval of the quasi-symmetrical left and right portion of the manikin shall be

±2 mm for the head and ±3 mm for the torso with respect to the plane of symmetry.

NOTE For measurements that include both hea
...

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