IEC 63034:2020

IEC 63034 ®
Edition 1.0 2020-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Microspeakers
Micro-haut-parleurs
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IEC 63034 ®
Edition 1.0 2020-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Microspeakers
Micro-haut-parleurs
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.160.50 ISBN 978-2-8322-8312-7

– 2 – IEC 63034:2020  IEC 2020
CONTENTS
FOREWORD . 6
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms . 8
4 Conditions of measurement . 9
4.1 Rated measuring conditions . 9
4.2 Climatic conditions . 9
4.3 Normal measuring conditions . 9
5 Acoustical environment . 10
5.1 General . 10
5.2 Free-field conditions . 10
5.3 Half-space free-field conditions . 10
5.4 Simulated free-field conditions . 10
5.5 Half-space simulated free-field conditions . 10
6 Mounting of the microspeaker . 10
6.1 Mounting and acoustic loading of microspeaker units . 10
6.2 Mounting and acoustic loading of microspeaker systems . 11
6.3 Standard micro-baffle . 11
6.4 Measuring plane wave tube. 12
7 Positioning of microspeaker and measuring microphone . 13
7.1 Positioning of the microspeaker . 13
7.1.1 Rated geometrical condition . 13
7.1.2 Reference plane . 13
7.1.3 Reference point . 13
7.1.4 Normal vector . 13
7.1.5 Polar vector . 14
7.2 Measuring distance under free-field and half-space free-field conditions . 14
7.2.1 Far-field condition . 14
7.2.2 Single microspeaker unit (transducer) . 14
7.2.3 Multi-unit microspeaker systems . 14
7.3 Positioning of microspeaker and microphone in simulated free-field and half-
space free-field conditions . 14
8 Measuring equipment . 15
9 Accuracy of the measurement. 15
9.1 General . 15
9.2 Unwanted acoustic and electrical noise . 15
9.3 Accuracy of the mounting . 15
9.4 Accuracy of the measuring equipment . 15
9.5 Accuracy of acoustic environment . 15
10 Marking of terminals and controls . 15
10.1 General . 15
10.2 Positive terminal . 16
10.2.1 Characteristic to be specified . 16
10.2.2 Marking . 16

10.2.3 Method of testing . 16
11 Test signals . 16
11.1 General . 16
11.2 Steady-state sinusoidal signal . 16
11.3 Sinusoidal chirp signal . 16
11.4 Discrete multi-tone sinusoidal signal . 17
11.5 Broadband noise signal . 18
11.6 Narrow-band noise signal . 18
12 Preconditioning . 18
12.1 Acclimatization . 18
12.2 Pre-loading . 18
13 Electrical input impedance . 19
13.1 Electrical input impedance curve . 19
13.1.1 Characteristics to be specified . 19
13.1.2 Method of measurement . 19
13.2 Rated impedance . 19
14 Small signal parameters of the microspeaker . 19
14.1 General . 19
14.2 Characteristics to be specified . 20
14.2.1 Resonance frequency f . 20
s
14.2.2 DC resistance of driver voice coil R . 20
dc
14.2.3 Voice coil inductance L . 20
e
14.2.4 Total Q-factor Q . 20
ts
14.2.5 Electrical Q-factor Q . 20
es
14.2.6 Mechanical Q-factor Q . 20
ms
14.2.7 Mechanical compliance C . 20
ms
14.2.8 Moving mass M . 21
ms
14.2.9 Mechanical resistance R . 21
ms
14.2.10 Force factor Bl . 21
14.2.11 Equivalent air volume of a microspeaker unit compliance V . 21
as
14.2.12 Effective radiation area S . 21
D
14.3 Method of measurement . 21
14.3.1 General . 21
14.3.2 Laser ranging method . 21
14.3.3 Added volume method . 23
14.3.4 Added mass method . 25
15 Displacement . 25
15.1 Displacement curve . 25
15.1.1 Characteristics to be specified . 25
15.1.2 Method of measurement . 25
15.2 DC component X . 26
dc
15.2.1 Characteristics to be specified . 26
15.2.2 Method of measurement . 27
15.3 Distortion limited peak displacement X . 27
d
15.3.1 Characteristics to be specified . 27
15.3.2 Method of measurement . 27

– 4 – IEC 63034:2020  IEC 2020
15.4 Sinusoidal peak displacement X . 27
s
16 Amplitude frequency response . 28
16.1 Rated frequency range . 28
16.2 Frequency response . 28
16.2.1 Characteristic to be specified . 28
16.2.2 Method of measurement . 28
16.3 Mean sound pressure in a stated frequency band . 28
16.3.1 Characteristics to be specified . 28
16.3.2 Method of measurement . 28
16.4 Effective frequency range . 29
16.4.1 Characteristics to be specified . 29
16.4.2 Method of measurement . 29
17 Amplitude non-linearity . 29
17.1 Total harmonic distortion (THD) . 29
17.1.1 Characteristic to be specified . 29
17.1.2 Method of measurement for input voltages up to the rated sinusoidal
voltage . 29
th
17.2 Harmonic distortion of the n order . 30
17.2.1 Characteristic to be specified . 30
17.2.2 Method of measurement for input voltages up to the rated sinusoidal
voltage . 30
17.3 Total higher-order harmonic distortion components (HOHD) . 30
17.3.1 Characteristic to be specified . 30
17.3.2 Method of measurement for input voltages up to the rated sinusoidal
voltage . 30
th
17.4 Modulation distortion of the n order (where n = 2 or n = 3) . 31
17.4.1 Characteristic to be specified . 31
17.4.2 Method of measurement . 31
18 Listening test . 32
18.1 Listening test for normal operation . 32
18.2 Listening test for irregular distortion . 32
19 Input voltage/Electrical power . 33
19.1 Rated noise voltage/power . 33
19.1.1 Characteristic to be specified . 33
19.1.2 Method of measurement . 33
19.2 Short-term maximum input voltage/power . 34
19.2.1 Characteristic to be specified . 34
19.2.2 Method of measurement . 34
19.2.3 Protective devices . 34
19.3 Long-term maximum input voltage/power . 35
19.3.1 Characteristic to be specified . 35
19.3.2 Method of measurement . 35
19.3.3 Protective devices . 35
19.4 Rated sinusoidal voltage/power . 35
19.4.1 Characteristic to be specified . 35
19.4.2 Method of measurement . 35
20 Environmental testing . 36
20.1 Temperature ranges . 36
20.1.1 Performance-limited temperature range – Characteristic to be specified . 36

20.1.2 Damage-limited temperature range – Characteristic to be specified . 36
20.2 Humidity ranges . 36
20.2.1 Relative humidity range – Characteristic to be specified . 36
20.2.2 Damage-limited humidity range – Characteristic to be specified . 36
20.3 Cold storage . 36
20.3.1 Characteristic to be specified . 36
20.3.2 Method of measurement . 36
20.4 Cold usage . 36
20.4.1 Characteristic to be specified . 36
20.4.2 Method of measurement . 36
20.5 Dry heat storage . 37
20.5.1 Characteristic to be specified . 37
20.5.2 Method of measurement . 37
20.6 Dry heat usage . 37
20.6.1 Characteristic to be specified . 37
20.6.2 Method of measurement . 37
20.7 Thermal shock (rapid change of temperature with prescribed time of

transition) . 38
20.7.1 Characteristic to be specified . 38
20.7.2 Method of measurement . 38
20.8 Steady damp heat . 38
20.8.1 Characteristic to be specified . 38
20.8.2 Method of measurement . 38
21 Stray magnetic fields . 39
21.1 General . 39
21.2 Static components . 39
21.2.1 Characteristic to be specified . 39
21.2.2 Method of measurement . 39
21.3 Dynamic components . 40
21.3.1 Characteristic to be specified . 40
21.3.2 Method of measurement . 40
22 Physical characteristics . 41
22.1 Dimensions . 41
22.2 Weight . 41
23 Design data . 41
Bibliography . 42

Figure 1 – Standard micro-baffle . 11
Figure 2 – Standard micro-baffle with sub-baffle . 12
Figure 3 – Plane wave tube . 12
Figure 4 – Rated geometrical conditions of the microspeaker. 13
Figure 5 – Electrical input impedance curve of the microspeaker . 23
Figure 6 – Peak and bottom values of displacement . 26
Figure 7 – Displacement curve . 26
Figure 8 – DC component of displacement . 27
Figure 9 – Block diagram of test setup . 33
Figure 10 – Measuring apparatus for stray magnetic field . 39

– 6 – IEC 63034:2020  IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MICROSPEAKERS
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
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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.
International Standard IEC 63034 has been prepared by IEC technical committee 100: Audio,
video and multimedia systems and equipment.
The text of this International Standard is based on the following documents:
CDV Report on voting
100/3107/CDV 100/3211/RVC
Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://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.

– 8 – IEC 63034:2020  IEC 2020
MICROSPEAKERS
1 Scope
This document specifies the characteristics of microspeakers as well as the relevant test
methods on microspeakers using steady-state sinusoidal signals, sinusoidal chirp, multi-tone
or noise. The main characteristics include, but are not limited to, impedance, displacement,
amplitude frequency response, distortion, and power handling.
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 60268-1, Sound system equipment – Part 1: General
IEC 60268-2, Sound system equipment – Part 2: Explanation of general terms and calculation
methods
IEC 60268-21:2018, Sound system equipment – Acoustical (output based) measurement
IEC 60268-22:2020, Sound system equipment – Electrical and mechanical measurements on
transducers
IEC 61260-1, Electroacoustics – Octave-band and fractional-octave-band filters – Part 1:
Specifications
3 Terms, definitions and abbreviated terms
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
3.1 Terms and definitions
3.1.1
microspeaker
loudspeaker, the radiating element (diaphragm or other radiator) of which is not greater than
40 mm
Note 1 to entry: The term "microspeaker" applies to the microspeaker unit (transducer) and also to passive
microspeaker systems, which consist of one or more transducers provided with acoustical structures (e.g. chamber,
port, aperture).
3.2 Abbreviated terms
HOHD higher-order harmonic distortion

4 Conditions of measurement
4.1 Rated measuring conditions
For convenience, this document specifies how sound system equipment shall be set up for
measurement. Normal measuring conditions are defined in this document. To obtain the actual
conditions for measurement, some values (known as "rated conditions") shall be taken from the
manufacturer’s specification.
These rated conditions are not subjected to measurement, but they constitute the basis for
performing the measurements to determine the other characteristics.
The following rated conditions are of this type, and shall be stated by the manufacturer:
– rated impedance;
– rated sinusoidal voltage or power;
– rated noise voltage or power;
– rated frequency range;
– rated geometrical condition;
– rated climatic conditions.
NOTE A full explanation of the term "rated" is provided in IEC 60268-2. See also term 151-16-08 in IEC 60050-
151:2001.
4.2 Climatic conditions
IEC 60268-1 states that tests should be carried out in the following environment in order to
prevent the influence of temperature and humidity that can affect the properties of
microspeakers.
– ambient temperature: 15 °C to 35 °C;
– relative humidity: 25 % to 75 %;
– air pressure: 86 kPa to 106 kPa.
And the standard climatic conditions for arbitration testing are as follows:
– ambient temperature: (23 ± 1) °C;
– relative humidity: 48 % to 52 %;
– air pressure: 86 kPa to 106 kPa.
4.3 Normal measuring conditions
The microspeaker is understood to be working under normal measuring conditions when all the
following conditions are fulfilled:
a) the acoustical environment is specified, and chosen from the ones specified in Clause 5;
b) the microspeaker to be measured is mounted in accordance with Clause 6;
c) the microspeaker is positioned with respect to the measuring microphone and the walls in
accordance with Clause 7;
d) the measuring equipment suitable for determining the desired characteristics is connected
in accordance with Clause 8;
e) the microspeaker is supplied with a specified test signal, in accordance with Clause 11, of
a stated voltage U, within the rated frequency range in accordance with 16.1. If required,
the input power P can be calculated from the equation: P = U /R, where R is the rated
impedance in accordance with 13.2.

– 10 – IEC 63034:2020  IEC 2020
5 Acoustical environment
5.1 General
Acoustical measurements will be made according to one of the acoustic field conditions
specified in 5.2 to 5.5, and the choice shall be stated in the results.
5.2 Free-field conditions
Acoustical conditions that approach those of free-field space are used. The environment shall
be considered satisfactory where the sound pressure decreases with the distance (r) from a
point source according to the 1/r law, also with an accuracy of ±0,5 dB in the measured sound
pressure amplitude in the region occupied by the sound field between the microspeaker and
the microphone during the measurement.
Free-field conditions will prevail over the whole frequency range of measurement. If the
environment (e.g. an anechoic chamber at low frequencies) does not fulfill these free-field
conditions over the entire frequency range of the measurement, the manufacturer shall state
the valid frequency range.
5.3 Half-space free-field conditions
Acoustical conditions where a free-field (see 5.2) exists in a half space are used. These
conditions will be met with a reflecting plane of sufficient size so that the sound pressure from
a point source mounted on the surface of the plane decreases in the manner specified in 5.2.
5.4 Simulated free-field conditions
Acoustical conditions where the simulated free-field conditions are equivalent to those of free
space for the period required for a measurement are used.
The conditions will be met in any environment (e.g. large rooms with no obstructions) where
sound emitted by the microspeaker reflected from any surface or object in the environment does
not reach the measuring microphone before the completion of the direct sound measurement.
Any such reflection reaching the microphone will be excluded from the measurement by gating
or other means.
NOTE Under such conditions, successive measurements are separated by time intervals sufficient for the sound
pressure level to decrease to a negligible value owing to reverberation within the space.
5.5 Half-space simulated free-field conditions
Acoustical conditions where the simulated free-field (see 5.4) exists in a half-space are used.
These conditions shall be used when a reflecting plane, forming one boundary of a simulated
free-field environment, is of sufficient size that no reflections from its edge reach the measuring
microphone during the measurement.
NOTE Under such conditions, successive measurements are separated by time intervals sufficient for the sound
pressure level to decrease to a negligible value owing to reverberations within the space.
6 Mounting of the microspeaker
6.1 Mounting and acoustic loading of microspeaker units
The performance of the drive unit (transducer) is determined by the properties of the unit itself
as well as its acoustic loading. The acoustic loading depends upon the mounting arrangement,
which shall be clearly described in the presentation of the results.

One of the following three types of mounting shall be used:
a) in free-field, a standard micro-baffle, the drive unit with/without a specified measuring
enclosure;
b) in free-field, in free air, the drive unit with/without a specified measuring enclosure;
c) in free-field, a plane wave tube, the drive unit with/without a specified measuring enclosure;
d) in half-space free-field, the drive unit flushed with a reflecting plane, the drive unit
with/without a specified measuring enclosure.
NOTE Mounting condition a) approaches a half-space free-field down to a lower limiting frequency, the value of
which depends on the chosen measuring distance. Measurements made at frequencies below this limiting value can
be used for comparative purposes only.
The structure and material of a specified measuring enclosure (known as a "box"), whose net
volume is usually no more than 1 cm , shall be specified by the manufacturer and indicated in
the results.
6.2 Mounting and acoustic loading of microspeaker systems
Microspeaker systems are usually measured without an additional baffle. If the manufacturer
specifies a special type of mounting for the microspeaker system, this shall be used for the
measurement. The mounting method used shall be specified in the results.
6.3 Standard micro-baffle
The standard micro-baffle shall be made of a plane front surface that is acoustically reflective.
The micro-baffle shall have the dimensions shown in Figure 1.
The standard micro-baffle should be made of a material of adequate thickness to ensure
negligible vibration. The edge of the radiating element should be substantially flush with the
front of the micro-baffle. This may be achieved by using a thin, rigid sub-baffle with or without
a chamfer, as shown in Figure 2.
Dimensions in millimetres
Figure 1 – Standard micro-baffle

– 12 – IEC 63034:2020  IEC 2020

a) Sub-baffle with a chamfer b) Sub-baffle without a chamfer
Figure 2 – Standard micro-baffle with sub-baffle
6.4 Measuring plane wave tube
The tube shown in Figure 3 shall be used. The tube shall be made with an acoustically reflective
material.
The diameter of the tube d shall be 1,5 to 2,5 times as large as the diameter of the radiating element to be
tube
measured. The length of the tube l shall be between 600 mm and 1 000 mm.
The tube shall be of a material with adequate stiffness to ensure negligible vibration.
The edge of the radiating element shall be substantially flush with the front surface of the end of the tube.
An appropriate sound absorbing material shall be used to remove standing waves that can occur in the tube. A
clearance l of between 150 mm and 200 mm and a length l of between 200 mm and 500 mm are recommended.
a b
The recommended material of the tube is PVC (vinyl chloride). The recommended material of sound absorbing
3 3
material is polyester fibre (density: approximately between 20 kg/m and 25 kg/m , total mass: between 14 g
and 30 g).
After mounting with plane wave tube, the fundamental resonance frequency of the drive unit shall not be changed by
more than 5 % and no additional resonance peak shall be generated in the electrical input impedance.
Figure 3 – Plane wave tube
7 Positioning of microspeaker and measuring microphone
7.1 Positioning of the microspeaker
7.1.1 General
The terms in 7.1 are specified by the manufacturer and cannot be measured.
7.1.2 Rated geometrical condition
NOTE This is a rated condition in accordance with 4.1.
The position and orientation of the diaphragm or other kind of radiator shall be stated using the
radiator’s reference point o , the normal vector n and the polar vector p as illustrated in
ref ref ref
Figure 4.
Figure 4 – Rated geometrical conditions of the microspeaker
7.1.3 Reference plane
A reference plane with respect to a physical feature of the microspeaker shall be specified by
the manufacturer.
The reference plane shall be used to define the position of the reference point o and the
ref
direction of the normal vector n .
ref
NOTE For symmetrical structures, the reference plane is usually parallel to the radiating surface at the rest position
of the microspeaker. For asymmetrical structures, the reference plane is better indicated by means of a diagram.
7.1.4 Reference point
A reference point on the reference plane shall be specified by the ma
...