2010GB/T 3241-2010 Electroacoustics.Octave-band and fractional-octave-band filters
1998GB/T 3241-1998 Octave-band and fractional-octave-band filters
1982GB 3241-1982 Octave and third-octave band filters used for the analysis of sound and vibration
GB 3241-1998 1/1 and 1/3 octave filters for sound and vibration analysis was changed to GB/T 3241-2010 Electroacoustics.Octave-band and fractional-octave-band filters.