短時間実効値による音楽ＣＤのジャンル別変動特性

Abstract

In the last decade, personal music players have become used by an increasing portion of the population, particularly young people. Music signal from such players has been a significant threat to hearing because it can reach very high sound volumes without quality loss. This paper describes music level characteristics with musical genres to discuss signal level variation. To estimate total quiet portion of music signal, short time root-mean-square values within 10ms are calculated every 5ms period from music CD. Frequency distribution curves of the short time rms is well expressed by a beta distribution. An index expressing music quietness is defined by the probability of strms going down below -6dB from its rms value. Some relationships between the -6dB probability and musical genres are indicated. It is concluded that the -6dB probability takes larger value in Classical, HipHop/Rap, Jazz and R&B genres than others.