Loudness
A subjective term for the sensation of the magnitude of sound. Generally a 10dB increase in sound pressure level is perceived as a doubling of subjective loudness. At low frequencies (20Hz to 200Hz) an increase of as little as 5-6 dB is perceived as a two-fold increase in the subjective loudness.
- Loudness is affected by sound pressure level
- Loudness is affected by frequency
- Loudness is affected by bandwidth
- Loudness is affected by temporal factors
- Very short duration sounds (<100 ms) have their loudness affected by duration
- The loudness of longer duration sounds is not affected by duration
- Loudness adaptation (ie reduction with prolonged exposure) is only observed in special conditions
Reference
Zwicker, E. (1958): Uber psychologische und methodische Grundlagen der Lautheit. Acustica 8, 237-258.
Eberhard Zwicker, Bertram Scharf, "A model of loudness summation", Psychological Review, Volume 72, Issue 1, January 1965, Pages 3-26
See also: Perceived Noisiness, Phon, Sound Pressure Level, Zwicker Loudness.
Subjects: Audio Noise & Vibration
- Weblinks:
- Introduction to Computer Music: An Acoustics Primer An introduction to acoustics for musicians - a well written clear introduction.