Detail of GB/T 7341.3-2024

Introduction of GB/T 7341.3-2024

Electroacoustics - Audiometric equipment - Part 3: Test signals of short duration 1 Scope This document specifies a means of describing the physical characteristics, in terms of electrical waveforms, of audiometric reference and test signals of short duration and methods for their measurement. The object of this document is to ensure that audiometric stimuli of short duration are specified and measured in the same way and that the calibration of equipment using such signals is carried out using defined methods. This document does not describe the method of use of short-duration test signals. 2 Normative references The following documents contain requirements which, through reference in this text, constitute provisions 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. ISO 389-6 Acoustics - Reference zero for the calibration of audiometric equipment- Part 6: Reference threshold of hearing for test signals of short duration Note: GB/T 4854.6-2014 Acoustics - Reference zero for the calibration of audiometric equipment - Part 6 : Reference hearing threshold levels for test signals of short duration (ISO 389- 6:2007, IDT) IEC 60318-1 Electroacoustics - Simulators of human head and ear- Part 1: Ear simulator for the measurement of supra-aural and circumaural earphones Note: GB/T 25498.1-2010 Electroacoustics - Simulators of human head and ear - Part 1: Ear simulator for the calibration of supra-aural earphones (IEC 60318-1:1998, IDT) IEC 60318-3 Electroacoustics- Simulators of human head and ear- Part 3: Acoustic coupler for the calibration of supra- aural earphones used in audiometry Note: GB/T 25498.3- 2010 Electroacoustics - Simulators of human head and ear - Part 3: Acoustic coupler for the calibration of supra-aural earphones used in audiometry (IEC 60318-3:1998, IDT) IEC 60318-4 Electroacoustics - Simulators of human head and ear- Part 4: Occluded- ear simulator for the measurement of earphones coupled to the ear by means of ear inserts IEC 60318-5 Electroacoustics - Simulators of human head and ear- Part 5: 2 cm3 coupler for the measurement of hearing aids and earphones coupled to the ear by means of ear inserts Note: GB/T 25498.5-2017 Electroacoustics - Simulators of human head and ear - Part 5:2 cm3 coupler for the measurement of hearing aids and earphones coupled to the ear by means of ear inserts(IEC 60318-5:2006, IDT) IEC 60318-6 Electroacoustics - Simulators of human head and ear - Part 6: Mechanical coupler for the measurement of bone vibrators 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 short-duration signal signal having a duration of less than 200 ms 3.2 click transient acoustic or vibratory signal whose frequency spectrum covers a broad frequency range, produced by applying a single rectangular electrical pulse to the terminals of the transducer 3.3 tone-burst gated sinusoidal signal having a duration of less than 200 ms Note 1: Figure 3 shows a reference tone-burst (see 4.3). Note 2: A tone-burst is sometimes called a "brief tone" or a "tone pip". 3.4 instantaneous frequency 3.5 chirp short-duration signal in which the instantaneous frequency between two specified values varies monotonically for the duration of the signal 3.6 upward chirp chirp which presents the low frequency components in the chirp before the high frequency components 3.7 broadband chirp chirp that has a specified electrical amplitude spectrum covering at least 5 octaves of the normal audible frequency range, Note: See Figure 5.

Contents of GB/T 7341.3-2024