This standard specifies the commonly used frequencies in acoustic measurements. It is not applicable to music. GB 3240-1982 Common frequencies in acoustic measurements GB3240-1982 standard download decompression password: www.bzxz.net
This standard specifies the commonly used frequencies in acoustic measurements. It is not applicable to music.
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1 Introduction National Standard of the People's Republic of China Preferred frequencies for the acoustical measurement Preferred frequencies for the acoustical measurement1.1 This standard specifies the preferred frequencies for acoustical measurement. It is not applicable to music. This standard is compiled with reference to the international standard ISO2661975 "Acoustics - Preferred measurement frequencies". UDC534.321 GB3240-82 1.2 In acoustical measurement, since frequency series with various frequency intervals are used, it is difficult to compare the test results with each other. Therefore, it is necessary to specify a frequency series relative to a certain reference frequency, and thereby determine some commonly used frequencies in acoustical measurement. This not only makes it easier to compare the measurement results, but also allows the design of special acoustic test instruments and printed drawings of frequency characteristics for these frequencies, bringing more convenience to acoustic measurement and analysis. 1.3 In acoustics, the frequency of 1000Hz is very important. For example, it is determined as the reference frequency of the loudness level (see national standard GB3239-82 "Subjective and objective expression of the strength of sound and noise in air"). Therefore, this frequency is specified as the reference frequency of the frequency series used in acoustic measurement. 1.4 For the frequency intervals in the frequency series, they are generally constant increments and constant percentage increments. The former forms an arithmetic progression, and the latter is a geometric progression. This standard recommends the use of a geometric frequency series with constant percentage increments as the frequency interval in general acoustic measurements. For some situations where constant increments are required as the frequency interval, an arithmetic frequency series can be used. 1.5 In acoustic measurements, the frequency interval of the frequency series with constant percentage increments as the frequency interval is often an octave or its fraction (such as 1/3 octave). However, in the subsonic and ultrasonic frequency ranges, it is more appropriate to use a power of 10 as the frequency interval. The frequency series determined by these two frequency intervals are very close. Therefore, the commonly used frequencies specified in this standard are all selected from the series specified in the international standard ISO3-1973 "Preferred Numbers-Preferred Number Series". The exact values of these commonly used frequencies can be calculated from the following formula: f=1000×10-/10 where n is a positive or negative integer (n=0, ±1, ±2, ±3.) 2 Common frequencies in acoustic measurements 2.1 Common frequencies in acoustic measurements are listed in Table 1, which also gives the nominal values and exact values. 2.2 For commonly used frequency values with octave or 1/3 octave as frequency intervals, the symbol "×" is used in the corresponding row. 3 Use of commonly used frequencies 3.1 When discrete frequencies are required for measurement data and design and manufacture of electroacoustic devices, the frequency values in the table should be selected. 3.2 For bandpass filters or bandpass acoustic signals, the frequency values in Table 1 should be the geometric center frequencies of their passbands. Issued by the National Bureau of Standards on June 8, 1982 Implemented on July 1, 1983 Common frequencies Nominal values Additional notes: Accurate values Octave GB324082 Common frequencies in acoustic measurement Octave This standard is reviewed and approved by the National Technical Committee for Acoustics Standardization. National Technical Committee for Acoustics Standardization Nominal values 100000 125000 160000 Chairman: Ma Daxian, Vice Chairmen: Yu Bo, Wu Dasheng, Xu Weiyi. This standard is proposed by the Subcommittee on Fundamentals of Acoustics. Subcommittee on Fundamentals of Acoustics Chairman: Ma Daxian, Vice Chairmen: Wu Wenqiu. Exact valuebzxZ.net 125893 158489 Octave Octave Members: Wei Rongjue, Du Lianyao, Guan Dinghua, Li Peizi, Zhang Jia, Yang Jingang, Fang Zhi, Li Lin, Liu Dongsheng, Jiang Xiaohua, Chen Xiancai, Zhang Ruwei. This standard was drafted by the "Acoustic Terminology" and other standard compilation groups. Group leader: Ma Daxian, group members (in order of surname strokes): Yu Bo, Lü Ruyu, Shen, Wang Chenghao, Li Zhen, Yang Jingang, Zha Jixuan, Xu Weiyi, Qian Zuwen, Zhang Ruwei. Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.