Some standard content:
National Standard of the People's Republic of China
Guide to hearing aid standards
This standard is equivalent to IEC118-10 "Hearing aids Part 10: Guide to hearing aid standards". 1 Subject content and scope of application
UDC 534.77 (083.1)
GB11452-89
This standard is used to introduce and check the existing national standards for hearing aids. Different types of hearing aids require different test methods, so a guide is needed to ensure the correct use of each national standard. In addition, it is necessary to use this guide to check the existing national standards related to hearing aids and use it as a glossary of terms used in these national standards. The purpose of this standard is to provide guidance for the corresponding standards for various hearing aids. The text includes a glossary of terms and the scope of application of each standard, and proposes specific measurement requirements. The classification method of hearing aids is given according to the maximum saturation level. 2. Vocabulary of terms
This vocabulary list all the terms defined in the hearing aid standard system of my country (national standards or recommended standards). 2.1 Acoustic gain (under specified frequency and standard working conditions) (GB6657 "Measurement method of electroacoustic characteristics of hearing aids") The difference between the sound pressure level measured at the test point and the sound pressure level generated by the hearing aid in the simulator, which can also refer to GB7263 "Quality inspection of hearing aids after delivery", adopting the specified pressure level method, SJ/7.9115 "IF combination test of hearing aids" (non-standard simulator ②) For the sound combination mentioned in G11455 "Incompletely worn on the body of the hearing aid". In accordance with Articles 3.2.3 and 3.2.4 of this standard,
-force sensitivity (SJ/79143.2 "Method for measuring characteristics of hearing aids with bone vibrator output"), the ratio of the vibration force generated by the hearing aid on the force coupling to the sound pressure at the reference point under the specified frequency and working conditions. 2.3 South---force sensitivity level (AMSL) (SJ/Z 9143.2) The ratio of the force sensitivity to the reference sensitivity -12Pa
, multiplied by 20 with the logarithm of 10 as the base, expressed in decibels. Note: To calculate the sound sensitivity level (AMSL) measured in accordance with this standard, the following formula can be used: ASI = decibel number of the output level OFI. (with IV as reference) AMS1. = OFI.-input sound level. 2.4 Rise time (GB6659 "Measurement method of electroacoustic characteristics of hearing aids with automatic gain control circuits only") The time from the moment when the input signal level suddenly rises to a certain specified decibel number to the moment when the sound pressure of the hearing aid with AGC circuit stabilizes and makes it within 2 dB of the steady-state sound pressure level of the input. 2.5 Normal dynamic range rise time (GB6659) The time required for the initial input sound pressure level to increase by 25 dB from 55 dB. 2.6 Automatic gain control (AGC) (GB6659) A method for automatically controlling the gain in a hearing aid using the input signal envelope value or other signal parameters as a function. 2.7 Human body model rotation axis (GB11453 "Method for measuring the performance of hearing aids under simulated actual working conditions") A straight line that passes through the reference point and falls in the symmetric direction of the human body model. The human body model is installed in a position corresponding to the human body standing, then the axis will be a vertical line (the human body model can be rotated about this axis). z.8 Azimuth of sound radiation (#) (GR11453) The angle between the symmetry plane of the human body model and the plane determined by the rotation axis and the test axis. When the human body model faces the sound source, the azimuth of the sound radiation is defined as 0°; when the right side of the human body model faces the sound source, the azimuth is defined as 90; when the left side faces the sound source, the azimuth is defined as 270°.
GB11452--89
2.9 Basic sound level frequency response curve (SJ/Z9143.2) The output sound level frequency response curve obtained when the gain control is set at the reference test gain micro-position and the input sound level is 60dH. 2.1 Basic frequency response curve (GB6657) The frequency response curve measured at the reference test gain setting when the input sound pressure level is 60dB. 2.11 Headphones (SI/ISO 9143.2)
Electromechanical transducer used to vibrate the earphones and produce hearing sensation. 2.12 Comparison method (G6657)
A measurement method in which the hearing aid and a microphone used to measure the sound pressure in the sound field are placed at two scientifically equivalent points in the sound field. 2.13 Comprehensive frequency response curve (GH6657) The gain control is placed at the reference test gain position and the input sound level is set. The obtained frequency response curve is used to show the input-output characteristics of the entire working range of the hearing aid. 2.14 Sound compression ratio (the ratio of the input sound pressure level value specified by the enterprise) (GB6659) The ratio of the input sound level difference to the corresponding output sound pressure level difference under steady-state conditions: both differences are expressed in decibels. 2.15 Dynamic sound pressure characteristics (GB6659)
When the input sound signal of a predetermined frequency and a predetermined sound pressure level is modulated by a rectangular envelope pulse with a fixed pulse amplitude, the output pressure envelope expressed as a function of the time.
2.16 Ear canal extender (GB11453)
When connecting the H part of the ear simulator and the outside of the ear simulator (reference surface), the outer part of the ear canal is simulated.
2.17 Ear plug simulator (GI11453)
A device that provides a connection between the ear plug and the ear plug. For example, an ear plug without a connecting tube or similar device. 2.18H simulator (GB6657, GB11453, SI/Z9[50 "Measurement of sound source and sound source cavity simulator") is a device for measuring the output of headphones under specified frequency range and specified load conditions. The basic structure includes the main cavity, the load terminal and the calibrated microphone. The microphone is selected so that the sound on the transmitter is approximately the opposite of the sound reflected on the eardrum of the human ear: (α) (GB11453)
The distance between the reference plane of the human model and the test axis. When the head of the human model faces the sound source, the elevation angle is defined as +90. When the test position is away from the reference plane. The elevation angle is defined as). 2.20 Frequency response (GB6657)
The maximum voltage level produced by the hearing aid in the simulator under specified test conditions is the frequency response number. See the notes and distances in Section 2.1.
2.21 Full-stop gain (GB6657, GB7263) The gain of a hearing aid under essentially linear input/output conditions when the gain control is at the maximum value (full stop) and other controls are at specified positions at a specified frequency or as a function of frequency.
2.22 Full-stop analog insertion gain (GB11453) The analog insertion gain that a hearing aid can achieve when the gain control is at the maximum value (full stop) and other controls are at specified positions. 2.23 High-level rise time (GB6659) When the initial input sound pressure level is 60dB, the time to increase the input sound pressure level by 4(dB. 2.24 High-level recovery time (CGB6659) When the initial input level is 100dB, the time to recover after the input sound pressure level is reduced by 40dB. 2.25 Automatic gain control lower limit or user-controlled gain control (GH6659) acts on the hearing aid to give it a lower gain than the line. 2 = 0.5dB input and output level. GB11452-89
2.26 Human body model (human head and torso simulator) (GB11453) The human head and torso simulator extends from the top to the waist to simulate the sound diffraction generated by the head and torso of an average adult. The head includes a wing simulator and at least one plugged ear simulator. 2.27 Human body model non-blocked sound response (MDR) (GB11453) When not using a hearing aid , the sound pressure level at a specified frequency in the ear simulator is expressed as a function of the azimuth and/or elevation angle. 2.28 The difference between the sound level in the unobstructed ear simulator and the reference sound pressure level. It is a function of the position of the human model. 2.29 The gain response (MFR) of the human model unobstructed (GB11453) The gain of the unobstructed ear of the human model is expressed as a function of frequency, which is a function of the position of the human model. 2.30 The maximum sound gain at a specified frequency (GB6657) The highest possible sound gain that a hearing aid can achieve at a specified frequency. 2.31 Maximum magnetic field intensity (GB11454 "Magnetic field intensity of audio induction circuit for hearing aids") The magnetic field intensity corresponding to the maximum average value of the speech signal of the system for a short time (relative to the integration time used in the average process of about 0.125s) within the specified range,
2.82 Maximum sound pressure level (GB 6657)
The maximum position of the saturated voltage level response line, 2.33 Maximum sensitivity (maximum magneto-acoustic sensitivity level) (GB6658 "Measurement method for electro-acoustic characteristics of hearing aids with inductive pickup coil input") The maximum output level that a hearing aid can achieve under basically linear input conditions at a specified input magnetic field strength and a specified frequency. All possible control positions of the hearing aid and the orientation of the hearing aid relative to the test field can enable the inductive receiving coil to have the maximum magnetic induction value.
2.34 Force coupler (SJ/Z9143.2)
This device is designed to provide a specified force resistance for an actuator with a constant static force. It is equipped with a force-to-electric transducer to measure the force level on the contact surface between the vibrator and the force coupler. 2.35 Nominal reference test increase (GB7263) Nominal reference test increase It refers to the gain when the sound pressure level out of the acoustic coupling cavity is adjusted to 15dB below the nominal reference test OSPL at the reference test frequency when the hearing aid uses an input sound pressure level of 60dB. If the gain provided is not achieved, the full-speed gain is used as the nominal reference test gain. Note: According to the definition, the nominal reference test gain measured at an input level of 60dB is equal to the nominal reference test SP minus 75dR
2.36 nominal reference test gain control position or nominal reference test gain position (GB7263). At this gain control position, the nominal reference test gain given by the manufacturer according to the hearing aid product is obtained. 2.3 Reference test level OSPL9 (GB7263) The nominal value of OSPI at the reference test rate given by the manufacturer 2.38 Vibration simulator (SJ/Z9150) The part of the ear canal that simulates the inner end of the ear canal from the end of the capsule to the eardrum. 2.39 Output level (FL) (SJ/Z9143.2) The vibration force level of the specified frequency produced by the bone conduction ear of the test aid on the force coupler. 2.40 Output force level (OFI.) (SJ/Z9143.2) with an input level of 90dB (OFL95) The OFL produced at the specified frequency when the input voltage level is 90dH and the hearing aid gain control is in the full range. 2.41 Output sound pressure level frequency response (SPL) (SJ/Z9143.2) Under the specified test conditions of the specified input sound pressure level, the OFL generated by the hearing aid on the sound amplifier is expressed as a function of frequency. 2.42 Input sound pressure level x 90dB Output sound pressure level at a specified frequency (or frequency) (OSPLg) (GB6657) At the specified frequency (or frequency) point, the gain controller is in the full position, and other controllers are in the position to obtain maximum gain. When the input sound level is 90dB, the pressure level can be measured by the simulator. Its abbreviation is OSPI0 (or OSPL0 frequency). (Also can be referred to as Note () and Note ② of Article 2.1). 2.48 Ear wing simulator (GB11453)
GB11452--89
County has a device that approximates the shape and size of an average adult ear wing. 2.44 Symmetrical human body simulation (GB6657) The human body model is divided into two symmetrical planes, left and right, through the human body model reference point. 2.45 Sound pressure method (GB6657)
A measurement method that uses a sound pressure type control sensor to control the input sound pressure level at the hearing aid inlet to substantially eliminate the diffraction energy of the hearing aid.
Note: Also available in GB7263 and SJ29143.2. 2.46 Recommended magnetic field strength half-mean value (GB6657) Within the specified area, it corresponds to the long-term half-mean magnetic field strength of the speech signal applied to the system. 2.47 Recovery time (GB6659)
The time interval from the moment when the specified input signal level suddenly drops to the specified lower decibel number (under the condition of increasing the signal, the amplifier with AGC reaches a steady-state output) to the moment when the output sound pressure level of the hearing aid stabilizes at the lower steady-state sound pressure level 2dB.
2.48 Recovery time within normal dynamic range (GB 6659) When the initial input pressure level is 80dB and the input pressure level is reduced by 25dB, the recovery time is H. 2.49 Reference input sound pressure level (GH11153) The free field sound pressure level at the test point before the human body model is placed. 2.50 Reference direction (of hearing aid) (GB6657) The direction of the hearing aid in the test box relative to the sound source, which is consistent with the direction of the hearing aid when the user faces the sound source in actual application. 2.51 Reference direction of human model (GB11453) A half-surface perpendicular to the axis of rotation and containing the reference point of the human model. 2.52 Reference point (of hearing aid) (GB6657) A point selected on it to determine the position of the hearing aid. 2.53 Reference point (of subject or human model) (GB11453) The bisector of the line connecting the centers of the two channels (the intersection of the upper and lower channels). 2.54 Reference position of the human model in the test space (GB 11453) The position of the human model in the test space meets the following conditions: The reference point is consistent with the test point!
Both the square angle and the low angle are Cen.
2.55 Reference test frequency (GR6657)
At this frequency point, adjust the position of the gain control. To obtain the same frequency as OS The reference test frequency is usually 160Hz. For some hearing aids (such as high-pitch hearing aids), a higher reference test frequency of 2500 can be used. If 25(H7) is used, it will be stated on the test report card. 2.56 Reference test gain (GB6657)
The sound gain when the hearing aid gain control is in the reference test gain control position at the reference test test frequency. 2.57 Reference test gain control position (GB6657) At the reference test frequency, the input sound pressure level is product B, adjust the hearing aid gain control so that the output unpressure level in the ear simulator is 15±1 lower than OSPL. gain position. If the gain control cannot reach this position, the full-scale gain control position can be used.
2.58 Sampling level (frequency response curve) (GB6657) The highest sound level that the hearing aid can achieve in the H simulator at the specified starting frequency (or expressed as a function of frequency). Note: The saturation sound level does not necessarily occur at the highest input sound pressure level. GB11452-89
Sound sensitivity level) (GB6657)
2.59 Sensitivity (magnetic sensitivity level) (GB6657)
The sound pressure level in the coupling cavity under basically linear input-output conditions at a specified input magnetic field strength and a specified frequency. 2.60 Simulated insertion gain (SIG) (GBI1453) The amount of sound generated by the hearing aid in the ear simulator The difference between the positive sound level in the ear simulator without the hearing aid. It is equal to SISG (2.64) minus MFR (see 2.29) and is a function of the position of the human body model. 2.61 Simulated insertion directivity response reduction (SIDR) (GB11453) The difference between the directivity response of the simulated actual working conditions and the directivity response of the human body model without blocking. 2.62 Simulated input gain frequency response (SIGFR) (GB11453) The simulated insertion gain is expressed as a function of frequency. 2.63 Simulated actual working conditions directivity response (SISDR) (GB11453) The positive sound level produced by the hearing aid in the ear simulator at a specified frequency, a specified gain value and a specified input level is expressed as a function of the angle of rejection and/or the rejection.
method, this test is performed on the human body model.
2.64 Simulated actual working condition gain (SISG) (GB11453) The sound pressure level produced by the hearing aid in the headphone simulator is the difference between the reference input sound pressure level and the reference input sound pressure level. It is a function of the position of the human model. Note: This test is performed on the human model.
2.65 Simulated actual working condition gain frequency response (SISGFR) (GB11453) Simulated actual working condition gain is expressed as a function of frequency. 2.68 Simulated actual working condition method (GB6657) In order to simulate the acoustic impact of long-term wearers, the hearing aid is installed on the simulated human head and torso for testing. 2.67 Simulated actual working condition OSPL (GB11453) The reference input sound pressure level is 90dN, and the gain control is at the maximum compensation (full range). The output sound pressure level produced by the hearing aid in the ear simulator at the specified frequency.
Note: This test is performed on a human body model.
2. OSFI-9 frequency response under simulated operating conditions (GB11453) The OSPL under simulated operating conditions is expressed as a function of frequency. Design: This test is performed on a human body model 1.
2. The magnetic field frequency response specified in 69 (GB11453) is fed to the system at a constant input signal level, and the magnetic field intensity changes relative to 1000Hz. 2. The magnetic field area specified in T0 (GB11453) is the area required for placing the induction coil of the hearing aid under normal use. Within this area, there is a magnetic field strength that meets the recommended specifications.
General: The specified magnetic field avoidance area is a few pairs of circuits. 2.71 The vector components of magnetic field strength (GB 11453) are specified for many purposes. For example, the hearing aid user is located in a large space, and the vertical component of the magnetic field is the most important quantity. In this case, the specified vector components refer to the multiplicative components. Other magnetic field components are also important and should be stated in the report. And indicate the value of the component. www.bzxz.net
For other situations, such as using a small transmitting coil in close contact, the maximum sensitivity method can be used. In this case, the specified vector components refer to the scene where the detection is carried out, and the maximum sensitivity method of the user's inductive pickup coil. 2.72 Steady input - output diagram (GB6657) Under the conditions of specified frequency and gain control settings, a graph is drawn showing the functional relationship between the output level and the input voltage level, both of which are expressed in a linear scale.
2.73 Substitution method (GB 6657)
The method of measuring the sound field by alternately using a microphone to measure the free field shore pressure..com2.74 Power supply voltage (GB 6657)
GB11452—89
The terminal voltage of the hearing aid battery when the hearing aid switch is turned on. 2.75 Test axis (GB 11453)
The connecting line between the test point and the center of the sound source.
2.76 Test plane (for the measurement of the wavefront uniformity of the white field) (GR11453)
The plane perpendicular to the test axis and containing the test point. 2.77 Test point (GB 6657)
The test point is a position in the test box. It is both the point for measuring the white field sound pressure level and the position for placing the reference point of the tested hearing aid.
Note: See 2.79.
2.78 Test point (magnetic field) ((GB 6658)) A point in the test chamber where the magnetic field strength is specified. 2.79 Test point (measured with a human body model) (GB11453) A reproducible position in the test space where the sound pressure level is measured when the human body model is not in place. The human body model reference point is specifically determined for the test.
Column: See 2.77:
2.80 Test space (GB6658)
refers to the space where the hearing aid is placed during the test, with the center of the space being the test point. The magnitude and direction of the spatial magnetic field strength are within the specified limits.
2.8F Vibration force level (force level) (SI/Z9143.2) The ratio of the effective value of the force of the transmitted vibration to the reference value of 1! N, take the logarithm with the base 10 and multiply it by 20, and express it in decibels. 3 Standards related to hearing aids
This chapter lists the hearing aid standards and other standards related to hearing aids and their scopes. 3.1 Hearing aid standards
3.1.1 GB6657 Part 0.
This standard describes the measurement of the physical characteristics of air conduction hearing aids based on the current field technology and using human ear simulators. 3.1.2 GB 6658.
The purpose of this standard is to describe the method of determining the physical performance of hearing aids using a sensing threshold in an audio magnetic field. 3.1.3 GB 6659
This standard applies to any type of hearing aid with an automatic gain control (AGC) circuit. This standard provides a unified method for specifying dynamic and static characteristics and their measurement for hearing aids with AGC circuits. This standard includes devices that have the characteristics of compressing and/or limiting the envelope of the listening signal, and also includes devices that control the long-term average output.
a) AGC is used to achieve compression, or reduce the dynamic range of the output sound to maintain the integrity of the input sound. b) AGC circuits replace clipping devices and are often used for limiting. At higher input levels, the de-amplification effect occurs when the input/output characteristic becomes flat, and the limiting effect is the main means to prevent the hearing aid from entering the listener's ear with excessive sound. This standard does not include:
a. Expanders.
b. Clipper, cuts off the signal peak above a certain level. This device is basically stable and can keep the input signal from being shaped..com AGC circuit,
GB11452-89
Note: AGC circuits with very short recovery time, especially at low frequencies, will cause considerable distortion and should be paid special attention to. 3.1.4 CB 11455
The purpose of the standard is to describe the method of determining the overall electroacoustic performance of hearing aids that are not fully worn on the listener. Such hearing aids are used for the rehabilitation of hearing-impaired people.
The methods specified in this announcement give data on the measurement of parameters that are fully covered by GB6657, namely: frequency response,
air conduction gain,
acoustic input;
gain and output control
-internal noise of the equipment;
-electrical input sensitivity and output power:
-the total effect of the transmission path in a system where the microphone and the earphone (or multiple microphones and earphones) are connected without wires. Other measurements other than those in national standards such as GB 6657. 3.1.5 GB 11454
This standard applies to audio induction loops that generate alternating magnetic fields and provide input signals to hearing aids with induction pickup coils. 9.1.6 Scope of GB6661 "Nipple connectors for insert earphones"
This standard applies to insert earphones so that the earphones can be matched with the eardrum inserted into the ear canal. 3.1.7 SJ/Z9143.1 "Characteristics of the electrical input circuit of hearing aids". Scope and purpose
This standard specifies the electrical characteristics, marking and safety characteristics of the external electrical input of personal hearing aids to ensure the compatibility of external electrical signal sources or electroacoustic signal sources.
This standard does not include the circuit of signal transmission (CROS) components of the whole system or the stand-alone circuit of signal transmission (Bi-CROS) hearing aids.
3.1.8 GB 7263
This standard applies to the measurement of the performance of air conduction hearing aids so that the measured characteristics can be compared with the values specified by the manufacturer. This standard does not involve mechanical or environmental tests, and generally cannot be used as a data exchange on the characteristics of hearing aids, nor can it be used as a basis for personal selection of hearing aids.
Note: In this standard, the terms "home" and "buyer" are used only as the two parties to the hearing aid agency that want to apply the technical standard. 3.1.9 GB11453
This standard applies to the measurement of hearing aid performance. The measurement method is crucial when estimating the wearer's influence on the acoustic performance of a hearing aid, especially when the results are used in the selection of hearing aids. Compared with hearing aid standards (such as GB 6657 and GB7263) that are used for type testing and quality control, the information obtained using this standard will be more closely related to the selection of hearing aids. The method specified in this standard requires a human model device to simulate the wearer's head and the role of the head. In order to meet the requirements of the human model, it is necessary to establish some guidelines for measurements under simulated actual working conditions of the hearing aid. This standard describes these recommended methods. Note: The accuracy and repeatability of the results obtained under simulated actual working conditions may not be as good as expected by the field technology according to GB6657. For this reason, it does not include other application conditions for measuring hearing aid parameters under simulated actual working conditions other than those described in 1. 3.1.10 SJ/Z9143.2 GB11452-89 specifies the measurement method of hearing aid characteristics using bone detectors. 3.1.11 G16660 "Symbols, other signs and related design on hearing aids" This standard is used for symbols and other signs on hearing aids and related equipment to identify control files and provide information related to technical functions and characteristics. Related equipment should be understood to include the following devices: Interrupter equipment, not completely worn on the wearer: a training device: combined equipment; plug-in type machine; other accessories.
3.2 Other standards related to the hearing aids
3.2.1 GB 5365 "Hearing aid plug size" standard
This standard applies to hearing aid plugs and gives information: two-pin polarized plug
three-pin polarized plug.
This standard gives the above dimensions and the tolerances to ensure the replacement. 3.2.2SJ/Z 9145
Scope and purpose
The purpose of this standard is to describe the physical properties of air conduction hearing aids in the frequency range of 2005000Hz with the coupling cavity of headphones added together. Hearing aids use a plug (such as a molded or similar device) to connect the machine to the human ear. The coupling cavity described is the development of a 2cm coupling cavity.
The application of this coupling cavity has not achieved the actual performance of the hearing aid in the human body, but IEC recommends using it as a convenient method for exchanging physical data and specifications of hearing aids.
3.2.3GB7342 "IEC Temporary Reference Coupler for Headphone Calibration" Scope
This standard describes a temporary reference coupler with a certain acoustic impedance, used to calibrate audiometers and other equipment in the frequency range of 125~8000Hz.
The sound pressure generated by the headphones in the coupler is generally not equal to the sound pressure generated in the human ear. This standard only provides a simple tool for the exchange of audiometer specifications and calibration of test equipment. 3.2.4GB7614 "Wideband IEC Simulator for Headphone Calibration" Scope
This standard gives the specifications of the artificial ear with a frequency band of 20~10000Hz, which is used to calibrate the on-ear headphones without sound leakage. This standard does not apply to the calibration of ear-type headphones. 3.2.5 Force couplers for measuring resonators International Standard Scope 1) 1 Details I1C 373:
This standard specifies the requirements for force couplers used to calibrate bone conduction audiometers and for measuring resonators and bone conduction hearing aids in the frequency range of 125 to 8000 Hz.
3.2.6 Temporary head and head simulator for acoustic measurements of air conduction hearing aids (to be determined) Specification GB 11452-89
This international standard describes a human model that will simulate the acoustic effects of hearing aid performance on the human body, including diffraction. The human model is mounted on the torso extending from the waist to the waist. The head has ear wings and a cylindrical cavity with a normal impedance limit. The microphone is placed at the position corresponding to the eardrum of the person being measured. 3.2.7 SJ/7. 9150
This standard specifies a plugged H simulator for calibrating H aids with the pressure at the eardrum of the human ear in the frequency range of 100 to 10,000 Hz. The design of the plugged H simulator also serves as the basis for the future extension to the design of simulating the entire ear canal, so that the I
4 Types of measurement methods
Different parts of IC118 require different types of measurements. The basic differences between these measurements are as follows; 4.1 The self-marketing measurement of hearing aids has been standardized in GB6657. It requires good accuracy and small tolerances, and the measurement results are compared and evaluated by a wide range of techniques. They are quite different from the results obtained by specific listeners. The plugged H simulator adopts S"/? .9150. 4.1.1 The difference between the measurement results obtained using the IEC reference coupling SJ/9145 and the blocking simulator SJ/9150 will vary with the type of machine under test and its coupling conditions: the typical frequency of the machine under test is given in the attached A using the standard H model. 4.2 Standardized measurement description for product quality control and checking delivery tolerances" GB7263. The measurement method for short test spaces is simpler than the requirements of GB6657I.
S】%9145 small description This coupling cavity is a simple device for routine testing. Self-calibrated mountain line! The mountain line after calibration will show differences, which depends on the influence of the hearing aid on the field. 4.3 GB11453 small description: Measurement on a human body model simulating a grown-up wearer: The human body model includes the plugged-ear simulator of 4.1 and the injury simulator to be standardized. The frequency response curves obtained by connecting GH6657 to the color field will be closer to the results obtained on the average person, but they are still very different from the results obtained by using the specified subjects under actual working conditions. The measurement accuracy described in GB6657 is higher than that of GB 11453. 5 Intended use of IEC announcement
Table 1 gives the measurements that can be performed and the types of use of each measurement set. The use of the measurement functions is divided into the following: technical comparison, use evaluation:
product control, delivery tolerance
procurement selection, pre-fitting selection, training and learning. Oil: Pre-fitting starts with the appropriate calibration of the three hearing aids. According to the data provided by the document, the selection of the appropriate personal hearing aid type can be carried out! Be careful when interpreting this data (table). Table
Sound sea use
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2.OSP.g--H line
simulate actual working conditions
GB7263
meaning welcome!
GB11453
meaning i: use
5, full-scale gain frequency response
6. Simulate actual working conditions gain frequency response (SISGFR)
7, simulate human gain frequency response
(SIGFR)
man-made model response (MFR)
9. Full-scale power level
Xiao including frequency response curve
11. Store frequency response curve
12. Basic power level frequency load
13: Simulation batch actual working conditions benefit
(SISG)
Simulated insertion increase (SIG)
15. Human body model directivity response
16. Simulated industrial working conditions directivity response
17. Simulated human body directivity response
(SISDR)
18. The influence of tone cavity low gain on the frequency response
19. The influence of recording control position on the frequency response of the power level
20. The influence of the full-range control position on the long-range
21. Gain control ratio
22. The influence of power supply voltage on full-range gain
23. The influence of bleeder internal resistance on full-range gain
24. The influence of power supply conductance SFT
25. Battery electrical appliances
GB6657
GB11452--89
Continued Table 1
GB7263
Intended use
GR11453
Intended use
Cifu use
Its standard excess
SJ/Z9143.2
SJ/7 9143.2
SJ/7 9143.2
SJ/Z 9143.2
SJ/Z 9113.2
Intended use
26. Amplitude nonlinearity
27. Internal sound produced by the device
28. Input characteristics of the device
29. Maximum sensitivity of the induction sound line
30. Change of induction sound line sensitivity at position MT and t
31. Frequency response curve of induction pickup
32. Automatic gain control (AGC)
33. Trade name and other mark
34. External input
35. Machine plug size
36. Magnetic field in the frequency induction loop
37: Hearing aid plug
6 Classification of hearing aids
GB6657
GB11452—89
Continued Table 1
GB7263
Articles of use
GB11453
Intended use
Standard liquid
SJ/2 9143.2
SJ/7. A143.2
GB 6658
SJ/Z9143.2
GB6658
GR6658
GB 6658 :
GB6659
GB6660
SI:z 9143,1
GB6661
GR11454
GB5365
向便爬
The maximum saturated sound pressure level is one of the main characteristics of air conduction hearing aids. It will play an important role in selecting hearing aids for the impaired. Therefore, it is recommended to use the maximum saturated sound pressure level as a single parameter as the basis for the classification of hearing aids. The quantity used for classification is the highest output sound pressure level produced by the ear simulator S19150. All hearing aid controls and input sound pressure levels and frequencies are set to the permitted level. Hearing aids are divided into the following five categories for every 10dB increase in output sound pressure level. 6.1 Output sound pressure level (OSPF.) Classification
It is recommended to classify hearing aids as follows (see Table 2). 2
Sound pressure level, JB
105-114
115~124
125～134
Not, due to the difference in the material, the hearing aid is between the two adjacent categories, and the two categories can be used. Deliberate use
Technical comparison.
Evaluation purpose.
Product control and delivery tolerance.
GB11452—89
Purchase selection and pre-matching selection or training and teaching.
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