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Acoustics—Procedures for the measurements of real-ear acoustical characteristics of hearing aids

Basic Information

Standard ID: GB/T 20242-2006

Standard Name:Acoustics—Procedures for the measurements of real-ear acoustical characteristics of hearing aids

Chinese Name: 声学 助听器真耳声特性的测量方法

Standard category:National Standard (GB)

state:in force

Date of Release2006-05-08

Date of Implementation:2006-11-01

standard classification number

Standard ICS number:Metrology and Measurement, Physical Phenomena >> 17.140 Acoustics and Acoustic Measurement

Standard Classification Number:General>>Metrology>>A59 Acoustic Metrology

associated standards

Procurement status:ISO 12124

Publication information

publishing house:China Standards Press

Plan number:20030828-T-491

Publication date:2006-11-01

other information

Release date:2006-05-08

drafter:Dai Genhua, Tang Huide, Li Xiaodong

Drafting unit:Institute of Acoustics, Chinese Academy of Sciences, Tianjin Hearing Aid Factory

Focal point unit:National Technical Committee on Acoustic Standardization

Proposing unit:Chinese Academy of Sciences

Publishing department:General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China Standardization Administration of China

competent authority:Chinese Academy of Sciences

Introduction to standards:

This standard specifies the measurement methods and requirements for the real ear acoustic characteristics of hearing aids. The purpose is to ensure that the measurements made on a given hearing aid and the human ear have basically the same results under the conditions of following the methods described in this standard and using equipment that meets the requirements of IEC61669. The measurement of the real ear characteristics of hearing aids uses non-linear or analytical processing techniques, and the results are only valid for the test signals and test conditions used. The measurement should be carried out in accordance with the recommendations of the hearing aid manufacturer, because the manufacturer may require the use of test signals or test conditions with characteristics other than those specified in this standard. GB/T 20242-2006 Acoustics Measurement methods for real ear acoustic characteristics of hearing aids GB/T20242-2006 Standard download decompression password: www.bzxz.net
This standard specifies the measurement methods and requirements for the real ear acoustic characteristics of hearing aids. The purpose is to ensure that the measurements made on a given hearing aid and the human ear have basically the same results under the conditions of following the methods described in this standard and using equipment that meets the requirements of IEC61669. The measurement of the real ear characteristics of hearing aids uses nonlinear or analytical processing techniques, and the results are only valid for the test signals and test conditions used. The measurement should be carried out in accordance with the recommendations of the hearing aid manufacturer, because the manufacturer may require the use of test signals or test conditions with characteristics other than those specified in this standard.


Some standard content:

ICS 17. 140
National Standard of the People's Republic of China
GB/T 20242-2006/ISQ 12124:2001 Acoustics
AcntsticsProredures for the measurement of real-earacoustical eharacieristixs of hearing aids(1S0)12124-2001.JTT)
2006-05-08 Issued
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China Administration of Standardization of the People's Republic of China
2006-11-01 Implementation
Normative references
Terms of use
Measurement of the test chamber
5 Test environment
5.1 Ambient conditions
Acoustic performance of the test chamber
5.1 Field characteristics
6 Preparation of test chamber
Ju Ruisen
Set up the test chamber
For the test chamber Instruction
Creation method and step
and micro method
micro test signal
recipient's position
test person's position
household field payment point selection
get quantity point delivery
output device's adjustment coupon combination
7.10 WuT no hearing response (RELR) business line
no hearing aid stealing [RE curve
real ear response (RER mountain line
real tower secret tower stealing (RE) registration line.
?.1 point power response (REAR) disconnection
its ear power gain (REAG curve
7,5 real ear plug tower benefit RF1G> mountain line| |tt||8 Data record
Appendix A (optional appendix)
Measurement method of the location of the measuring point of the probe
GB/T2024220C6/I5012124,2001
This standard is equivalent to the standard IS013322:20 Acoustics Appendix A of this standard is an informative appendix.
This standard is issued by the Chinese Academy of Sciences.
GB/T20242-2006/1S(F12124:2001 Closed measurement method of hearing aid characteristics", this standard was issued by the Chinese Acoustics Standardization Technical Committee (SAC/TC17). This standard mainly starts Unit: Institute of Acoustics, Chinese Academy of Sciences and Tianfuka Hearing Aid Factory Main drafters of this standard: Genhua, Dun Ede, Li Dong. (B/T20242-2006/15) 12124:2001 Introduction
The performance of hearing aids in actual use may be different from the performance determined according to IECS0118-0 and 1F:Cin11%-7. The reason is that different human ears have different acoustic conditions and characteristics. Therefore, in order to make the hearing aid fit properly, the measurement method needs to consider the fit of different ears and the impact on the natural performance of the hearing aid. This method is called "ear measurement". It is not carried out in an unexpected sound environment. The accuracy and repeatability of the measurements made under these conditions are related to the sound field, test loop cable, test signal characteristics, the sound field, test loop, test signal characteristics, the control method, source position and data acquisition, analysis and presentation, and the wearer's performance. The standard specifies the test environment and methods for the real ear characteristics of hearing aids. It specifies the necessary test points and sound field reference points, defines the various language to be used, and describes the necessary measurement methods and requirements for the real ear characteristics of hearing aids. The purpose of this standard is to ensure that the measurements made on a given real ear produce the same results as those made on the human ear using the methods described in this standard and equipment that meets the requirements of IEC 6166. The sound quality of the device is measured by the linear point analysis method. The test results are given by the test multiples and test conditions used. The test should be carried out according to the construction and operation of the hearing aid. Special tests or parts other than those specified in this standard may be required before manufacturing.
2 Normative reference documents
The above-mentioned clauses become the full clauses of this standard through reference to this standard: Any reference document with a date of reference shall not affect all subsequent amendments (including errors) and revisions to the next standard. However, the cooperation of all parties involved in the research of this standard may make these documents applicable to the latest version. For products with a date of more than half, the latest version of this standard is applicable only to G71513 City Calibrator (GT1.17-1991, TE12:158) 1622 Scientific Lake Audiometry Method Part 1 and Non-Test Field Audiometry (TSD F253-2:1992)
1351969 Electroacoustic single H device true acoustic characteristics measurement equipment 3. Technical specifications and definitions
This standard uses the following terms and definitions:
test signal testslgna
the state signal at the reference point in the sound field.
subject
the hearing aid can be used in his/her ear, 3.3
change the test position of the subject
5mhiect festposifinn
The test subject can be positioned in the same position as the test subject. The test subject's head is raised, and its reference point falls on 1. The test axis is within the test position:
The test subject's reference point is the midpoint of the test subject's heart and mouth, see 1:
Note: The asymmetry of the head can be inferred only by the test point, and the test source can only be left, 1
GB/T20242—20D5/IS012124,20013.5
The test axis testaxis
Through the sound source, the test subject's sound source must be connected to the test point, see Figure 1.3.6
working dislance
working distance
the height of the sound source measured along the test subject's reference point, 1:3. 7
sound pressure levelsound pressureare level
the logarithm of the ratio of the sound pressure to the reference pressure multiplied by 2 with the base 10, in B. Note: These must not be specified as 2: μt.
the sound pressure level obtained in a given frequency band.
testsignalleveltestsignallevel
the level of the test signal is expressed in sound pressure level ().
Note: For broadband signals, the effective bandwidth is 3.10
allation
controls the frequency of the test signal so that its level does not deviate from the median value and changes to 3.11
bag test microphone (control microphone) refereacemicrupbuae (coatrullingmicruphunt) is used to determine the test hazard level in Xiemin, and/or to control the small microphone in the protection, see Figure 2.3. 12
sonndnet
the hole that makes the microphone enter the microphone when measuring and adjusting the microphone, sit, for the detection microphone with type (see 3, 15). The sound hole is a relatively large water exhaustion hole, 3. 13Www.bzxZ.net
sound field test point Fleld reference During equalization and/or testing, the reference point of the tester's pickup hole is the point at which the sound pressure level in the ear canal is measured, see Figure 2). 3.16 Test ear The test subject places the probe microphone pickup hole in the ear, 2. The rotation auxiliary line ayils afrotatinm
passes through the vertical line of the tester's reference point. The subject can rotate around it, see Figure 1. 3.18 Angle of incidence aalmuthangleofsoundnckence CB/T20242—2006/1S012124:2001" The actual angle between the plane of symmetry between the subject and the plane determined by the test line of rotation axis, Figure 1 Note: "When the test card faces the test object, the test angle is 3\. When the test object is facing the test object, the normal angle of the test object is -0\. When the test object's ear is facing away from the sound source, the normal angle of the test object is -3.19
The test plane Gubjectreferenetplane is also the plane of the test reference point, see Figure 1.3.20
The elevation angle of sound incidence tlevathonangleofsonndincidenceThe elevation angle of sound incidence between the test object and the test object is 1. Note: When the test object is pointing back to the sound source, the elevation angle of sound incidence is +9. When the test axis is in the test object's plane, the elevation angle of sound incidence is 0.3.21
Measurement point
measuremrnl 2.22
Test signal type
Test signal characteristics represented by its harmonic or time characteristics. 3.23
Concurrent equalizer (real-time equalizer) Real-time equalizer Measurement equalization made at any time based on the monitoring results of the test system 3.24
Stored equalizer Measurement made based on the previous sound field data record. 3.25
Survival method meuud
Uses a balanced measurement method. When recording the field data, the subject is placed at a distance from the test subject, and the reference microphone is placed at the test point. 3.26
Modified pressure method is a real-time or real-time measurement method: The reference microphone is placed just in front of the subject's head, but the sound reflection from the ear canal and other organs will affect the sound quality. The reference microphone is placed at the test point, and the height is determined by the position of the reference microphone to the test subject. The height (mm) is determined by the center of the ear canal opening above and below the test subject. 3.27
Different comparison method The reference microphone is placed at the test point, and the height (mm) is determined by the center of the ear canal opening above and below the test subject. The cloud test provides the method for obtaining the level and the result. Conditions: The sound pressure should be used during the three-phase test. 3.28
Real-ear unaided hearing response (REUR) reabearanakkedresponse abandons the specified measurement method for signal sensitivity. When the test is correct, the difference between the user pressure level at the designated measurement point and the test signal level is determined by the relationship between the normal and the rated frequency. B/T20242—2006/ISO12124.20013.29
Real-ear unaided hearing gain (RFtG) eal-eurwnidedguin When the ear is not raised, the difference between the user pressure level at the designated measurement point and the test signal level is determined by the frequency: The high-frequency signal should also be used when the effective level is 3. 30
Real ear plugging response (RFOR) reul-urueculudidrespanse at the specified intended signal level, when the hearing aid is not working, the relationship between the positive level and the test signal level at the measurement point (B). 3.31
Real ear plugging gain (HEX:)
rral ear oocnluded gadn
point when the hearing aid is not working, the relationship between the positive level and the test signal level at the measurement point () and the efficiency Note: Useful signal level, 3. 32
REAK: realearafdedresponse is measured in a given test signal level. It is a function of the sound output at the measurement point and the relationship between the additional sound level and the main frequency. 3.33
realearhearingaidpeden(RKAG)reaearaidedpaia is measured in a drum sound instrument and it is a function of the pressure line at the measurement point and the test signal level (non-US) and the frequency response. 3.34
real-ta Kerrinsertiongain(REIG) The sum of the decibels when the sound is not heard and when the sound is not heard (REIG = REAG - RRI frequency X system
Note, RAKKI. Must be in the same test pole, 3.35
Yunpan (gain plate> curve rehpanse/galncurveRHAR: RHIIR> or gain difference
based on the high-frequency sound characteristics of the spectrum chart: no 328~.34). For example, the branch-1 virtual sound (REAR) mountain load, 3.36
free sound Tield
in the inter-directional medium, the energy of the wave reaching the boundary can be ignored, 3.37
quasi-free sound field yuaxi-freesainndfleld in the isotropic medium, the boundary is affected by the acceptable market. 3.35
extended sensitive sound field dirfussouadield
sound energy is distributed evenly, the sound energy is transmitted by the heart, and the sound energy is transmitted by the heart. The sound energy is distributed evenly ... The test network equipment, test signal, film connection, rigid test environment, test subject's dynamic design and degree, help to understand the contact with the subject's ear canal, the tightness of the bubble and the influence of its body signal 1
To the surface:
The person's age
Test line:
The subject's multiple main points
.T is made;
The sound person's elevation angle.
First test surface:
The dynamic axis.
GR/T20242—2006/ISO12124.2001 Figure 1 Relative position of the test subject and the sound source
GH/T20242.-2006/1S012124:2G011-Hearing
Measurement point:
Marking:
Model of the microphone:
Production core!
Selection of measurement point:
Sound field reference point.
Figure 2 Hearing aid or ear mold, measurement point and sound field reference point 5 Test environment
5.7 Environmental conditions
The environmental conditions of the test case during the test should comply with the provisions of the equipment manufacturer. 5.2 Noise
The background noise in any test room shall not exceed 1dB of the measured result. The permitted user is related to the equipment used, the test signal level and the changed hearing aid. In all rated bands, the full test signal should be at least 10dB higher than the background sound level than any other type of test signal, and the test signal should reduce the current pressure level at the sound field test point to about B. Hearing aids with automatic gain control or other signal processing techniques may be affected by sounds that are not easily perceived by the tester. When testing such hearing aids, the required sound level at all times should be lower than the excitation level of the circuit using automatic gain control or other signal processing techniques, or when its effect on the measurement results exceeds 1%. 5.3 Acoustic performance of the test room The geometric dimensions of the test room and the acoustic conduction of the test instrument will affect the accuracy of the measured sound and the test signals used, the type of test hearing aids, and the frequency of reflections from it and from the sound waves. The choice of the test point should be close to both working points and should minimize the errors caused by reflections from it and from the sound waves.
5.4 Field characteristics
The three types of test fields (GB/T20242-2006/1501-2124:2001) are available for testing. All of them can provide a suitable test environment. Among them, the requirements for the acoustic field and the diffusion field are strict. In fact, it is impossible to always meet all the requirements of the acoustic field. The other type of market is more practical, but the size has an impact on the ability to determine and quantify the performance. The acoustic field used for the test should be The test shall allow the tester to be within 3B of the sound level required by the test assessment level control standard. Preparation of the test subject
6.1 Otoscope examination
A qualified professional shall inspect the test subject with a single eye to ensure that there is no excessive noise. The test subject shall be informed of any possible noise before the test is given: 6.2 Position of the test subject
The test subject shall be seated in a comfortable position that is convenient for the tester, unless otherwise specified by the equipment manufacturer: The test subject shall be seated at a minimum of 1.5 meters from the test subject.The azimuth angle is 15° and the incident elevation angle is 0° (see 1). The incident angle and the angle between 0° and 45° can be used. The test report should specify the position of the test subject in detail. 6.3 Instructions to the test subject
Information about the test method and steps should be clearly told to the test subject and should be fully understood by the test subject. The test subject should be required to keep quiet during the test and avoid unnecessary movements. The test subject should also be told that if he feels uncomfortable, he can stop the test at any time. 7 Test methods and steps
7.1 Equipment
All measurements of hearing aids and real ear products should be carried out using the measurement method in accordance with JFCG1659. 1.2 Calibration
Before the test, the equipment should be calibrated directly or indirectly according to the manufacturer's requirements in accordance with GB/T15173. 7.3 Equalization method
7.3.1 Open method - storage equalization
According to the manufacturer's instructions, record the sound signal of the test site at its reference point. Once the production environment changes, the record will be updated.
Note: The reading method requires a uniform sound field,
7.3.2 Quick positive sound pressure method - storage equalization
The tester sits in the test site, and according to the manufacturer's instructions, adjusts the relevant equipment and the required equipment level: and makes a record. The test book will be received by the test personnel> according to the company's instructions, change the position of the test site, and update the record if there is a change in the production site or environment. 7.3.3 The positive pressure method - real-time equalization is not performed separately and is preferably performed in conjunction with the test signal monitoring method because other methods may produce unreliable results if the test conditions are not careful. Other methods may be used in practice. 7.4 Test screening number 7.4.1 The measurement signal type is a pure signal with a narrow range of pure signal (such as pure sound, pitch-sensitive sound, etc.) or a signal with a micro-noise ratio (such as noise reduction, supportive sound, etc.). The type of test signal shall be in accordance with the manufacturer's instructions and recorded. 7.4.2 Selection of test signal level
For those with technical problems that the user can control or the system, special considerations should be made. The selection of test sound levels should take into account the safety and comfort of the subjects: For example, the sound level of the test instrument should be as low as possible in the working area where the instrument is tested. The characteristics of the hearing aid should be observed within the range of 0x10 and 0x10. It should be verified whether the change of the test signal level causes the same change at the five-level point. The lock should be used for the same period of time. The sound pressure level of the sound source on the sound source should be prevented from being transmitted to the subject by the sound source in the environment. 7
CB/T 20242—2006/1SD 12124,20017.5 Positioning of test subjects
During the entire measurement period, the test subject shall be the subject’s position: see 6.2), and the original recording time shall be used as the reference.
2. 6 Positioning of test personnel
Especially the test personnel shall respond to the requirements of the test signal level in the frequency and frequency field. 7.7 Selection of sound field reference points
The reference points can be determined according to the equipment manufacturer’s suggestions or based on the specific configuration of the equipment. The test points shall be within the test range. The test signal level at the test point can be changed within the test range.
Australia (REURREAR> depends on the selection of the measuring point. For linear receivers, RFI: has nothing to do with the field. Note that during the test, the receiver will not be placed in the test process. 7.8 Selection of measuring points
The position of the measuring point is adjusted so that it does not change within the range of 3. This clause has an absolute value of 2. For non-blocking earphones, the measuring point is usually required to be at least 6 meters away from the throat, while for standard earphones, it is also required that the measuring point is at least 5 meters away from the sound outlet. See Appendix A! When positioning the probe microphone hole to the measuring point, pay attention to ensure that it does not fall into discomfort. Tip: Avoid blocking or compressing the probe The soft tube microphone method: deep insertion point open and hearing protection device allowed to roll enough to meet the requirements, method 2: close! The inspection hole of the probe tube production. The determination of the hearing aid is prohibited because of the flood. 7.9 The hearing aid hearing aid is coupled with the test material. The hearing aid fee is used by the test subject's name on the ear: the high current group is free of detection: the market measurement point is required to avoid displacement and the effect or positive pursuit of the teaching tube of the device. It is recommended to install the new hearing aid on the ground. 7.10 Real ear hearing aid should be consulted by KECR by the brand
such as the ticket this way single belt production PEG design master that public by the field test point, the special type of hazard level and specification measurement point: the formation and measurement RA long time use relative.
for the "storage supply method, the test day Li test on the test point, in the certification of the sound test point certification a production signal, the test subject on the scene to see 7. 3, 1 and 7. 3, 2
Let the interviewee go to the next test site.
Write the test equipment to the required two points. Read the probe tube transmission path of the user to determine the appropriate follow-up point (see) in the device used, select the type of test information and common small level <see. 1.. Now the test subject is not fast
According to the equipment to make the recording R curve,
7.1F real ear unaided hearing average RELG> curve over
plan the result of the test with a good EI medicine design with so many test points Xie information level measurement points and the same as the European EAG.
For the storage average method, the old sensor is determined, and the mid-field information is recorded at the appropriate mid-field point. The total test subject is also present in 7. 3, 1 and 7.3, 2.
Place the test subject at the test position.
Place the test probe near the required sound field test point, position the probe probe hole to the measurement point (center) and select the type of test signal (7, 4.2!,6. The position of test personnel
Especially the test personnel should consult with the tester in the frequency and respond to the test signal level requirements. 7.7. The selection of sound field reference points
The sound field reference points can also be determined according to the equipment manufacturer's suggestions or based on the specific performance of the equipment. The test points should be reviewed and the most suitable test signal level should be within the test subject's state.
Australia (REURREAR> depends on the selection of the measuring point. For linear receivers, RFI: has nothing to do with the field. Note that during the test, the receiver will not be placed in the test process. 7.8 Selection of measuring points
The position of the measuring point is adjusted so that it does not change within the range of 3. This clause has an absolute value of 2. For non-blocking earphones, the measuring point is usually required to be at least 6 meters away from the throat, while for standard earphones, it is also required that the measuring point is at least 5 meters away from the sound outlet. See Appendix A! When positioning the probe microphone hole to the measuring point, pay attention to ensure that it does not fall into discomfort. Tip: Avoid blocking or compressing the probe The soft tube microphone method: deep insertion point open and hearing protection device allowed to roll enough to meet the requirements, method 2: close! The inspection hole of the probe tube production. The determination of the hearing aid is prohibited because of the flood. 7.9 The hearing aid hearing aid is coupled with the test material. The hearing aid fee is used by the test subject's name on the ear: the high current group is free of detection: the market measurement point is required to avoid displacement and the effect or positive pursuit of the teaching tube of the device. It is recommended to install the new hearing aid on the ground. 7.10 Real ear hearing aid should be consulted by KECR by the brand
such as the ticket this way single belt production PEG design master that public by the field test point, the special type of hazard level and specification measurement point: the formation and measurement RA long time use relative.
for the "storage supply method, the test day Li test on the test point, in the certification of the sound test point certification a production signal, the test subject on the scene to see 7. 3, 1 and 7. 3, 2
Let the interviewee go to the next test site.
Write the test equipment to the required two points. Read the probe tube transmission path of the user to determine the appropriate follow-up point (see) in the device used, select the type of test information and common small level <see. 1.. Now the test subject is not fast
According to the equipment to make the recording R curve,
7.1F real ear unaided hearing average RELG> curve over
plan the result of the test with a good EI medicine design with so many test points Xie information level measurement points and the same as the European EAG.
For the storage average method, the old sensor is determined, and the mid-field information is recorded at the appropriate mid-field point. The total test subject is also present in 7. 3, 1 and 7.3, 2.
Place the test subject at the test position.
Place the test probe near the required sound field test point, position the probe probe hole to the measurement point (center) and select the type of test signal (7, 4.2!,6. The position of test personnel
Especially the test personnel should consult with the tester in the frequency and respond to the test signal level requirements. 7.7. The selection of sound field reference points
The sound field reference points can also be determined according to the equipment manufacturer's suggestions or based on the specific performance of the equipment. The test points should be reviewed and the most suitable test signal level should be within the test subject's state.
Australia (REURREAR> depends on the selection of the measuring point. For linear receivers, RFI: has nothing to do with the field. Note that during the test, the receiver will not be placed in the test process. 7.8 Selection of measuring points
The position of the measuring point is adjusted so that it does not change within the range of 3. This clause has an absolute value of 2. For non-blocking earphones, the measuring point is usually required to be at least 6 meters away from the throat, while for standard earphones, it is also required that the measuring point is at least 5 meters away from the sound outlet. See Appendix A! When positioning the probe microphone hole to the measuring point, pay attention to ensure that it does not fall into discomfort. Tip: Avoid blocking or compressing the probe The soft tube microphone method: deep insertion point open and hearing protection device allowed to roll enough to meet the requirements, method 2: close! The inspection hole of the probe tube production. The determination of the hearing aid is prohibited because of the flood. 7.9 The hearing aid hearing aid is coupled with the test material. The hearing aid fee is used by the test subject's name on the ear: the high current group is free of detection: the market measurement point is required to avoid displacement and the effect or positive pursuit of the teaching tube of the device. It is recommended to install the new hearing aid on the ground. 7.10 Real ear hearing aid should be consulted by KECR by the brand
such as the ticket this way single belt production PEG design master that public by the field test point, the special type of hazard level and specification measurement point: the formation and measurement RA long time use relative.
for the "storage supply method, the test day Li test on the test point, in the certification of the sound test point certification a production signal, the test subject on the scene to see 7. 3, 1 and 7. 3, 2
Let the interviewee go to the next test site.
Write the test equipment to the required two points. Read the probe tube transmission path of the user to determine the appropriate follow-up point (see) in the device used, select the type of test information and common small level <see. 1.. Now the test subject is not fast
According to the equipment to make the recording R curve,
7.1F real ear unaided hearing average RELG> curve over
plan the result of the test with a good EI medicine design with so many test points Xie information level measurement points and the same as the European EAG.
For the storage average method, the old sensor is determined, and the mid-field information is recorded at the appropriate mid-field point. The total test subject is also present in 7. 3, 1 and 7.3, 2.
Place the test subject at the test position.
Place the test probe near the required sound field test point, position the probe probe hole to the measurement point (center) and select the type of test signal (7, 4.2!,
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