1 Scope
This part of GB/T 12060 specifies the method for measurement on headphones and earphones.
This part is applicable to headphones, headsets (headphone transmitter sets), earphones and earsets (earphone transmitter sets), 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 GB 8898-2011 or another appropriate standard;
——the characteristics of microphones of headsets, for which reference should be made to GB/T 12060.4;
——earphones and other devices for hearing aids, for which reference should be made to GB/T 25102.100;
——headphones for audiometry;
——headphones and other devices which form part of an active ear-defender system, although some of its provisions may be applicable.
2 Normative references
The following referenced documents are indispensable for the application 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.
GB/T 156 Standard voltage (GB/T 156-2007, IEC 60038: 2002, MOD)
GB/T 531.1 Rubber vulcanized or thermoplastic — Determination of indentation hardness — Part 1: Durometer method (Shore hardness) (GB/T 531.1-2008, ISO 7619-1: 2004, IDT)
GB/T 2421.1 Environmental testing — General and guidance (GB/T 2421.1-2008, IEC 60068-1: 1988, IDT)
GB/T 2900.86-2009 Electrotechnical terminology — Acoustics and electroacoustics (IEC 60050-801: 1994, IDT)
GB/T 3769 Electroacoustics — Scales and sizes for plotting frequency characteristics and polar diagrams (GB/T 3769-2010, IEC 60263: 1982, IDT)
GB/T 3785.1 Electroacoustics — Sound level meters — Part 1: Specifications (GB/T 3785.1-2010, IEC 61672-1: 2002, IDT)
GB/T 6278 Simulated programme signal
GB/T 2002 Acoustics — Determination of sound power levels of noise sources using sound pressure — Precision methods for reverberation rooms (GB/T 6881.1-2002, ISO 3741: 1999, IDT)
GB/T 7584.1 Acoustics — Hearing Protectors — Part 1:Subjective method for the measurement of sound attenuation (GB/T 7584.1-2004, ISO 4869-1: 1990, IDT)
GB/T 8897.1 Primary batteries — Part 1: General (GB/T 8897.1-2008, IEC 60086-1: 2007, MOD)
GB/T 12060.2 Sound system equipment — Part 2: Explanation of general terms and calculation methods (GB/T 12060.2-2011, IEC 60268-2: 1987, IDT)
GB/T 12060.11 Sound system equipment — Part 11: Application of connectors for the interconnection of sound system equipment (GB/T 12060.11-2012, IEC 60268-11: 1987, NEQ)
GB/T 15212 Application of connectors for broadcast and similar sound system (GB/T 15212-1994, eqv IEC 60268-12: 1987)
SJ/Z 9140.1 Sound system equipment — Part 1: General (SJ/Z 9140.1-1987, idt IEC 60268-1: 1985)
SJ/Z 9150 Occluded-ear simulator for the measurement of earphones (SJ/Z 9150-1987, idt IEC 60711: 1981)
ISO 4869 3 Acoustics — Hearing protectors — Part 3: Measurement of insertion loss of ear muff type protectors using an acoustic test fixture
IEC Guide 106 Guide for specifying environmental conditions for equipment performance rating
IEC TR 60959 Provisional head and torso simulator for acoustic measurement on air condition hearing aids
ITU-T P.58 Series P Head and torso simulator for telephonometry
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
Note: Any device defined in 3.1 to 3.15 and their connector(s) for electrical input should be regarded as part of the transducer.
3.1
earphone
electroacoustic transducer by which acoustic oscillations are obtained from electric signals and intended to be closely coupled acoustically to the ear
Note: It is revised from the definition 801-27-18 in GB/T 2900.86-2009.
3.2
headphone
assembly of one or two earphones on a headband or chinband, the use of which may be optional (e.g. with intra-concha earphones)
Note: It is revised from the definition 801-27-20 in GB/T 2900.86-2009.
3.3
headset
headphones equipped with a microphone
Note: It is revised from the definition 801-27-21 in GB/T 2900.86-2009.
3.4
earset
earphones equipped with a microphone
3.5
insert earphone
small earphone that is attached directly to a connecting element, for example an earmould, inserted into the ear canal
Note: It is revised from the definition 801-27-22 in GB/T 2900.86-2009.
3.6
intra-concha earphone
small earphone that fits in the concha cavity, with its acoustic exit close to the entrance of the ear canal
Note: The definition of "insert earphones" is revised from the definition of "insert earphone" in GB/T 2900.86-2009, and put forward the definition of “intra-concha earphones”, because the measurement methods of these two types of earphones are different. The outer diameter (or maximum dimension) of intra-concha earphones is less than 25 mm, but it does not insert into the ear canal.
3.7
supra-aural earphone
earphone applied externally to the outer ear and intended to rest on the pinna
Note: It is revised from the definition 801-27-23 in GB/T 2900.86-2009.
Note 2: The outer diameter (or maximum dimension) of the supra-aural earphone is less than 45 mm.
3.8
supra-concha earphone
earphone intended to rest on the ridges of the concha cavity
Note: The outer diameter (or maximum dimension) of the supra-concha earphone is more than 25 mm and less than 45 mm.
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 General requirements
4.1 Classification, designation and coding
4.2 Marking of terminals, controls and polarity
5 Conditions for specifications and measurements
5.1 Rated conditions
5.2 Standard conditions for measurement
5.3 Couplers and ear simulators
5.4 Measuring conditions for simulated programme signal
5.5 Loudness comparison conditions
5.6 Ear canal sound pressure level measurement conditions
6 Characteristic to be specified and their methods of measurement
6.1 Power supply
6.2 Electrical impedance
6.3 Input voltage
6.4 Input power
6.5 Sound pressure (level)
6.6 Frequency response
6.7 Amplitude non-linearity
6.8 Rated climatic conditions
6.9 External electric and/or magnetic field
6.10 Unwanted sound radiation
6.11 Sound attenuation
6.12 Crosstalk attenuation for multi-channel headphones
6.13 Rated application force
6.14 Physical characteristics, cables and connectors
7 Classification of characteristics
Annex A (Normative) Pinna simulators for measurements of headphones and earphones
Annex B (Normative) Specification and conditions of use of a microphone for use inside the ear canal
Annex C (Informative) Practical details of free-field comparison conditions
Annex D (Informative) Practical details of diffuse-field comparison conditions
Annex E (Informative) Practical details of the subjective comparison and ear canal sound pressure level conditions
Bibliography
Figure 1 Diagrammatic horizontal sections showing types of earphones and their spatial relationships with the pinna and/or canal entrance
Figure 2 Diagrams showing the four possible constructions: acoustically open or closed, and closed- or open-back
Figure 3 Illustrated measurement diagram by simulated programme signal
Figure A.1 Shape of the recommended pinna simulator
Figure A.2 Coordinate for the recommended pinna simulator
Figure A.3 Cross-sectional shapes and dimensions of the recommended pinna simulator (horizontal section)
Figure A.4 Cross-sectional shapes and dimensions of the recommended pinna simulator (vertical section)
Table 1 Classification of characteristics