Mass

The predominant frequency range or band which the bulk or body of a sound occupies. The term was introduced by Pierre Schaeffer as part of a typology of the sound object. The emphasis therefore is on mass as a perceptual or psychoacoustic variable. A sound's mass is what allows it to stay recognizable under transposition or transformation such as filtering.

See also: Formant, Grain, Sound Event, Spectrum. Compare: Timbre, Volume.

Mass is further distinguished by Schaeffer as tonal, complex or varied. For a note of stable intonation, perceived mainly in terms of pitch, the mass is said to be tonal, whereas for a fixed but extended frequency range, which cannot be identified by a single pitch, such as in a gong or broad band noise, the mass may be called complex. When the mass is variable in range, as with a glissando, it is termed varied.