CCIR ARM-weighting

CCIR ARM-weighting or CCIR 2 kHz-weighting — A type of weighting filter for sound level measurements. This curve derives from the CCIR 468-curve we’ve covered in WFTD previously. Dolby Laboratories proposed using an average-response meter with the CCIR 468-curve instead of the costly true quasi-peak meters used by the Europeans in specifying their equipment. They further proposed shifting the 0 dB reference point from 1 kHz to 2 kHz (in essence, sliding the curve down 6 dB). This became known as the CCIR ARM (average response meter), as well as the CCIR 2 kHz-weighting curve. (See: R. Dolby, D. Robinson, and K. Gundry, “A Practical Noise Measurement Method,” J. Audio Eng. Soc., Vol 27, No. 3, 1979)