Sound Quality Standards (Sound and Vibration Measurement Suite)

This topic discusses the standards with which the Sound Quality VIs comply.

When combined with any National Instruments DSA device, the appropriate microphone, and proper signal conditioning, the measured 1/3 octave spectrum complies with ANSI, IEC, and JIS standards. Furthermore, the SV Stationary Loudness and SV Time-Varying Loudness VIs convert the 1/3 octave spectrum to stationary and non-stationary loudness measurements in compliance with the following standards:

• ISO 532 (1975): Method B, for calculating the loudness of steady complex sounds for which one-third octave band analyses have been obtained
• DIN 45631 (1991): Procedure for calculating loudness level and loudness
• DIN 45631/A1 (2008): Calculation of loudness level and loudness from the sound spectrum - Zwicker method - Amendment 1: Calculation of the loudness of time-variant sound

Method B in ISO 532 specifies a procedure for converting 1/3 octave band sound pressure levels into critical band sound pressure levels and ultimately into an overall loudness level. Method B also provides the conversion from loudness level in phons to loudness in sones, which is the same formula given in the ISO/R 131 standard.