Audiometers -Part 3 : Auditory test signals of short duration for audiometric and neuro-otological purposes
Some standard content:
GB/T 7341.3—1998
This standard is formulated based on the International Electrotechnical Commission standard IEC645-3:1994 Audiometer Part 3: Short-duration auditory test signals for audiometry and neuro-otology. As this international standard is technically mature and widely promoted internationally, it will play a driving role in ensuring the uniformity of hearing values in my country. Therefore, it is used as an equivalent to adapt to the needs of international technical exchanges as soon as possible. GB/T7341, under the general title of "Audiometry", includes the following four parts: Part 1: Pure tone audiometer
Part 2: Speech audiometry equipmentWww.bzxZ.net
Part 2: Short-duration auditory test signals for audiometry and neuro-otology Part 4: Extended high-frequency audiometry equipment
From the date of implementation of GB/T7341.1—1998~GB/T7341.4—1998, the original GB7341—87 audiometer\ shall be invalid. Appendix A of this standard is the appendix of the specification. This standard was proposed by the National Technical Committee for Standardization of Electroacoustics and Audiovisual Equipment. This standard was approved by the National Institute of Metrology of China. The drafting unit of this standard is the National Institute of Metrology of China. The main drafters of this standard are Zhang Jucai, Shen Yang, Zhou Xinhao, Qiu Jianhua and Shuai Zhengping. This standard is entrusted to the National Institute of Metrology of China for interpretation. GB/T 7341.3—1998
IEC Foreword
1) IFC (International Electrotechnical Commission) is a worldwide standardization organization including all national electrotechnical committees (IEC National Committees). The purpose of IEC is to promote international cooperation on all issues related to standardization in the electrical and electronic fields. For this purpose and other activities, IEC publishes international standards. Its formulation work is entrusted to technical committees. Any interested EC National Committee may participate in this work. International, governmental and non-governmental organizations related to IEC may also participate in this formulation work. IEC and the International Organization for Standardization (ISO) work closely under the conditions determined between the two organizations. 2) Formal decisions or agreements on IEC technical documents drawn up by all National Committees with a particular interest in the subject matter express, as far as possible, international consensus on the subject matter involved. 3) They are published for international use in the form of recommendations, technical reports or guidelines and are accepted by the National Committees for this purpose.
4? In order to promote international unification, IEC National Committees explicitly participate in the use of IEC International Standards in their national and regional standards. Any differences between IEC International Standards and the corresponding national or regional standards should be clearly stated in the latter. This part of International Standard IEC 645 was prepared by IEC Technical Committee 29 "Electroacoustics" to form the first edition of IEC 645-3. The text of this standard is based on the following documents:
29(CO)214
Voting Report
29(CO)215
Full information on the approval of this standard can be found in the voting report shown in the table above. Under the general title, Audiometers, EC 615 consists of the following parts: Part 1 Pure tone audiometry Part 2: Speech audiometry equipment Part 3: Short duration auditory test signals for audiometry and neuro-otology Part 4: Equipment for extended high frequency audiometry Acoustic and vibratory short duration test signals for audiometry and neuro-otology This standard provides a method for specifying the use of short duration acoustic and vibratory test signals for audiometry and neuro-otology. Examples of common tests using such signals are recording of brain evoked potentials and evoked otoacoustic emissions. Reference broadband clicks and brief pure tones are also described in order to provide a basis for calibration and as a reference when there is no specific reason to use other signals. The measurement methods for acoustic and vibratory signals are introduced as a guide for psychoacoustic derivations involving air conduction and oscillatory stimulation. 1 Scope National Standard of the People's Republic of China Part 3: Auditory test signals of short duration for audiometric and neuro-otological purposes GB/T 7341.3—1998 IEC 645-3:1994 This standard specifies a method for describing the physical characteristics of short duration audiometric tests and references part numbers and their measurement. This standard also specifies a psychoacoustic method for determining the level of the test signal using hearing levels. A guide to use is included as a reference. This standard does not describe the use of short duration signals or specify waveforms for clinical use. The purpose of this standard is to ensure that the short-duration test stimulus is specified, measured by the same method, and calibrated by the specified method. 2 Reference standards
The provisions contained in the following standards become the provisions of this standard through reference in this standard. When this standard is published, the following versions are valid. All standards are subject to revision. Parties using this standard should explore the possibility of using the latest versions of the following standards: GB3785-83 Electrical and acoustic properties and test methods of sound level meters GB7614-87 Wideband real ear for calibrating hearing aids GB7342-87 IEC temporary reference coupler for use in audiometry headphones SJ/Z9144-87 IEC reference coupler for testing hearing aid earplugs SJ/29150-87 Cold ear canal simulation curtain for measuring earphones GB/T15951-1995 Small coupler for bone detector testing GB/T 7341.1-1998 Audiometer Part 1: Pure tone audiometer GB/T 16403-1996 Acoustic audiometry method Basic audiometry of pure tone air conduction and bone conduction thresholds
This standard uses the following terms:
3.1 Short-duration signal short-duratton Signal refers to a signal with a duration shorter than 200 ms.
3.2 Brief pure tone brief lone
refers to a sinusoidal signal with a duration shorter than 2010 ms, see Figure 1. Note: Brief pure tone is sometimes also called distinguishing tone. GB/T 7341. 3 - T998
Fall time
Figure 1 Time characteristics of a brief pure tone
3.3 Duration of a brief pure tone Duration of a brief pure tone refers to the time interval between the two half-amplitude points of the rising and falling parts of the envelope of a brief pure tone, see Figure 1. 3.4 Rise time and fall time of a brief pure tone The former refers to the time interval between the two points where the amplitude of the rising part of the envelope of a brief pure tone is 10% and 90%, and the latter refers to the time interval between the two points where the amplitude of the falling part is 90% and 10%, see Figure 1. 3.5 Click
A signal of instantaneous sound and vibration with a wide frequency spectrum. Note: Click is also called broadband click. 3.6 initial pressure or force wave of a click the first half of the positive pressure or force wave, whose amplitude is 0.5 times greater than the second half of the opposite polarity. 3.7 duration of initial pressure or force wave of a click the time interval between the two zero crossings of the initial pressure or force wave. 3.8 rondensation signal the overpressure relative to the ambient pressure produced by the initial pressure wave of a short duration signal, or the excess force produced in the plane at the output end of the transducer.
3.9 dilution signal the underpressure relative to the ambient pressure produced by the initial pressure wave of a short duration signal, or the underforce produced in the plane at the output end of the transducer.
3.10 Peak-to-peak equivalent sound pressure level vibration reduction force level (peak SPL/peak VFL) peaklopeakenulvalentsoundpressureorvbratoryforeelevtl(peSPL/peVFi.) A long duration sinusoidal signal, when input to the same transducer under the same conditions as described in Chapter 5, has the same peak-to-peak sound pressure or vibration force amplitude as the short duration signal. For a click, the long duration sinusoidal signal should have a frequency of 1000 Hz; for a brief tone, its frequency should be equal to the baseband of the brief tone, see Figure 2. Note
1 Technical proof "peak-to-peak equivalent acoustic pressure level" is often referred to as "peak equivalent acoustic pressure level". 2 The peak sound level of the brief stimulus is 3dB to 9dB higher than the peak-to-peak equivalent sound pressure level at any position, that is, 3dB for a stimulus that is completely symmetrical to the baseline. When it is completely on the - side of the zero level, it is 9dB.
4 Reference signal
CB/T 7341-3—1998
Figure 2 Measurement method of peak-to-peak equivalent sound pressure level or equivalent vibration force level of click sound For standardization and calibration, the following reference signals are described 4.1 Reference click sound
The reference click sound should be generated by strobing the transducer with a rectangular electric pulse (single-phase square wave) with a rise time and a fall time of less than 25: duration of (100+10)5.
4.2 Reference brief pure tone
The reference brief pure tone should be generated by exciting the transducer with a linear rise and fall of 1.6 cycles of the fundamental frequency each and lasting for 3 cycles (as shown in Figure 1). Each brief pure tone shall start with equal crossings of the same phase. Note: Two cycles with an amplitude from 0 to 100% of the phase of 1.6 cycles of linear rise\linear fall. 5 Calibration and measurement of short-duration signals
5.1 Instruments that generate short-duration signals shall give the following characteristics of the measurement basis and be reported by the manufacturer. 1. Type of reference signal used:
- Type of transducer and type of related ear simulator or force coupler, and the method of coupling the transducer to it; - Level generated in the ear simulator or force coupler, expressed as peak-to-peak equivalent sound pressure level or equivalent force level; level in B units: - Polarity of the electrical output signal (i.e. positive, negative, alternating or random initial phase), Note: In order to identify the polarity of the acoustic or vibration signal, the polarity of the measurement system including the transducer must be known. 5.2 The equipment shall be calibrated using the reference signal defined in Chapter 4. If other signals are used, the manufacturer shall state the difference between the reference level obtained by the signal and the reference level obtained by the corresponding reference signal defined in Chapter 4. 5.3 The acoustic characteristics of short-duration signals shall be measured on an artificial ear (GB7614) or an ear simulator (SJ/Z9150). If an acoustic coupling chamber (GB7342) is used for routine calibration, the manufacturer shall state the relationship between the measurement on a real ear or ear simulator (SJZ9144) and on the acoustic coupling chamber.
5.4 For short-duration signals provided by the sound field, the measuring microphone shall be placed at the test point when the listener is not in place. The reference point is the midpoint of the straight line connecting the entrances of the two ear canals of the listener at the test position. The measurement shall be in accordance with the requirements of a Type 1 sound level meter in GB/T3785. 5.5 Equipment that uses bone conduction to provide short-duration signals shall be calibrated using the reference signal defined in Chapter 4. For this purpose, the bone vibrator should be placed on the force coupler in accordance with GB/T15951 and connected in parallel with appropriate equipment for peak-to-peak voltage measurement. Note: A simple method for determining the peak-to-peak voltage is to connect an oscilloscope to the electrical output of the instrument and an amplifier connected to an appropriate acoustic chamber or force coupler, simulation or simulator.
6 Determination of signal level by hearing level
The acoustic or force calibration of the equipment can be supplemented by a psychoacoustic calibration expressed in hearing level. For this purpose, the listener's reference value is used.
GB/T 7341.3 -1998
The reference listening level so determined is related to the repetition rate of the short-duration signal. The short-duration signal should appear as a burst of at least 18 to 26 sounds. The repetition rate used to obtain the reference value should be 20 Hz. When the repetition rate used in actual application is different from 20 Hz, the reference value should be determined according to the above procedure and the repetition rate used. The reference hearing values obtained above are only related to the transducer used and do not need to be linked to any other type of transducer. 7 Instructions for use
Instruments that generate short-duration hearing test signals should provide instructions for use, which, in addition to the requirements of 10.2 of GB/T 7341.1, should also include the following information:
a) Type of hearing signal (such as clicks or short pure tones); b) Type of transducer and their headband force; c) Type of ear simulator or force coupler used for calibration and method of coupling to the transducer; d) Type of calibration (such as using peak-to-peak equivalent pressure level or vibration force). (1) The subjective relationship between the test signal and the reference signal in this document expressed in hearing levels: 1) The information required in 5.1, 5.2 and 5.3 should be stated GB/T 7341.3-1998
Appendix A
(Suggestive Appendix)
Art Examination Literature
(1) Recommended Standards for Short Latency Auditory Evoked Potentials. J. Clin. Neurophysiol. 1, pp. 3240 (1984) (2) DaV18, H. Auditory brainstem response: preference for rate-selective stimulation in sensory evoked potentials. International Conference on Standards for Auditory Brainstem Responses (Editors A, Starr + C. Rosenberg, M. Don and H. Davis), pp. t5-69, Centro Recerche cStudi, Amplifon, Milan (1984).
(3) Stapells, DR Picton, TW and Smith, AD Calibration of click intensity in sensory evoked potentials. International Conference on Standards for Auditory Brainstem Responses (Editors A. Starr, C. Rosenberg, M. Don and Davis), pp. 35-38, Centro Recerche eStudi, Amplifon, Milani 1984). (4) Stapell, DR, Picton, TW. and Smith, AD Normal hearing of clicks. J. Acoust. SocAm. 72, pp. 74-79(1982).3 The acoustic characteristics of short-duration signals should be measured on an artificial ear (GB7614) or an ear simulator (SJ/Z9150). If the acoustic coupling chamber (GB7342) is used for routine calibration, the manufacturer should explain the relationship between the measurement on the real ear or ear simulator (SJZ9144) and the measurement on the acoustic coupling chamber.
5.4 For short-duration signals provided by the sound field, the measurement microphone should be placed at the test point when the listener is not in place. The reference point is the midpoint of the straight line connecting the entrances of the two ear canals of the listener at the test position. The measurement should be carried out in accordance with the requirements of the Type 1 sound level meter in GB/T3785. 5.5 Equipment that provides short-duration signals using bone conduction should be calibrated using the reference signal defined in Chapter 4. For this purpose, the bone vibrator should be placed on the force coupler in accordance with GB/T15951 and connected in parallel with appropriate equipment for peak-to-peak voltage measurement. Note: A simple method of determining the bee-peak voltage is to connect an oscilloscope to the electrical output of the instrument and the amplifier to an appropriate acoustic coupling chamber or force coupler, emulator or simulator.
6 Determining the signal level by hearing level
The acoustic or force calibration of the equipment may be supplemented by psychoacoustic calibration expressed in hearing level. The reference listening level used for this purpose is
GB/T 7341.3 -1998
The reference listening level so determined is related to the repetition rate of the short-duration signal. The short-duration signal should appear as a burst of at least 18 to 26 tone lengths. The repetition rate used to obtain the reference value should be 20 Hz. When the repetition rate used in actual application is different from 20 Hz, the reference value should be determined according to the above procedure and the repetition rate used. The reference listening value obtained above is only related to the transducer used and there is no need to relate it to any other type of transducer. 7 Instructions for use
Instruments that generate short-duration hearing test signals should provide instructions for use, which, in addition to the requirements of 10.2 of GB/T 7341.1, should also include the following information:
a) Type of hearing signal (such as clicks or brief pure tones); b) Type of transducer and their headband force; c) Type of ear simulator or force coupler used for calibration and method of coupling to the transducer; d) Type of calibration (such as peak-to-peak equivalent pressure level or vibration force); (1) The subjective relationship between the test signal and the reference signal in this document expressed in hearing levels: 1) The information required in 5.1, 5.2 and 5.3 should be stated GB/T 7341.3-1998
Appendix A
(Suggestive Appendix)
Art Examination Literature
(1) Recommended Standards for Short Latency Auditory Evoked Potentials. J. Clin. Neurophysiol. 1, pp. 3240 (1984) (2) DaV18, H. Auditory brainstem response: preference for rate-selective stimulation in sensory evoked potentials. International Conference on Standards for Auditory Brainstem Responses (Editors A, Starr + C. Rosenberg, M. Don and H. Davis), pp. t5-69, Centro Recerche cStudi, Amplifon, Milan (1984).
(3) Stapells, DR Picton, TW and Smith, AD Calibration of click intensity in sensory evoked potentials. International Conference on Standards for Auditory Brainstem Responses (Editors A. Starr, C. Rosenberg, M. Don and Davis), pp. 35-38, Centro Recerche eStudi, Amplifon, Milani 1984). (4) Stapell, DR, Picton, TW. and Smith, AD Normal hearing of clicks. J. Acoust. SocAm. 72, pp. 74-79(1982).3 The acoustic characteristics of short-duration signals should be measured on an artificial ear (GB7614) or an ear simulator (SJ/Z9150). If the acoustic coupling chamber (GB7342) is used for routine calibration, the manufacturer should explain the relationship between the measurement on the real ear or ear simulator (SJZ9144) and the measurement on the acoustic coupling chamber.
5.4 For short-duration signals provided by the sound field, the measurement microphone should be placed at the test point when the listener is not in place. The reference point is the midpoint of the straight line connecting the entrances of the two ear canals of the listener at the test position. The measurement should be carried out in accordance with the requirements of the Type 1 sound level meter in GB/T3785. 5.5 Equipment that provides short-duration signals using bone conduction should be calibrated using the reference signal defined in Chapter 4. For this purpose, the bone vibrator should be placed on the force coupler in accordance with GB/T15951 and connected in parallel with appropriate equipment for peak-to-peak voltage measurement. Note: A simple method of determining the bee-peak voltage is to connect an oscilloscope to the electrical output of the instrument and the amplifier to an appropriate acoustic coupling chamber or force coupler, emulator or simulator.
6 Determining the signal level by hearing level
The acoustic or force calibration of the equipment may be supplemented by psychoacoustic calibration expressed in hearing level. The reference listening level used for this purpose is
GB/T 7341.3 -1998
The reference listening level so determined is related to the repetition rate of the short-duration signal. The short-duration signal should appear as a burst of at least 18 to 26 tone lengths. The repetition rate used to obtain the reference value should be 20 Hz. When the repetition rate used in actual application is different from 20 Hz, the reference value should be determined according to the above procedure and the repetition rate used. The reference listening value obtained above is only related to the transducer used and there is no need to relate it to any other type of transducer. 7 Instructions for use
Instruments that generate short-duration hearing test signals should provide instructions for use, which, in addition to the requirements of 10.2 of GB/T 7341.1, should also include the following information:
a) Type of hearing signal (such as clicks or brief pure tones); b) Type of transducer and their headband force; c) Type of ear simulator or force coupler used for calibration and method of coupling to the transducer; d) Type of calibration (such as peak-to-peak equivalent pressure level or vibration force); (1) The subjective relationship between the test signal and the reference signal in this document expressed in hearing levels: 1) The information required in 5.1, 5.2 and 5.3 should be stated GB/T 7341.3-1998
Appendix A
(Suggestive Appendix)
Art Examination Literature
(1) Recommended Standards for Short Latency Auditory Evoked Potentials. J. Clin. Neurophysiol. 1, pp. 3240 (1984) (2) DaV18, H. Auditory brainstem response: preference for rate-selective stimulation in sensory evoked potentials. International Conference on Standards for Auditory Brainstem Responses (Editors A, Starr + C. Rosenberg, M. Don and H. Davis), pp. t5-69, Centro Recerche cStudi, Amplifon, Milan (1984).
(3) Stapells, DR Picton, TW and Smith, AD Calibration of click intensity in sensory evoked potentials. International Conference on Standards for Auditory Brainstem Responses (Editors A. Starr, C. Rosenberg, M. Don and Davis), pp. 35-38, Centro Recerche eStudi, Amplifon, Milani 1984). (4) Stapell, DR, Picton, TW. and Smith, AD Normal hearing of clicks. J. Acoust. SocAm. 72, pp. 74-79(1982).
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