Interval of equivalence
The equave (/ˈiːkwɪv/ EE-kwiv or /ˈiːkwəv/ EE-kwəv), also called interval of equivalence, equivalence interval, formal octave[1][note 1]or pseudo-octave[2][note 1], is the interval such that pitches separated by it are considered psychoacoustically or formally equivalent and are elements of the same pitch class.
If a periodic scale has an equave, the equave is typically the same as the period or a multiple thereof.
Etymology
The term equave was coined by Inthar. It is a portmanteau of equivalence and octave.
Examples
- In octave-repeating scales, the equave is typically 2/1.
- In Bohlen–Pierce, the equave may be taken as 3/1.
- In edfs, the equave may be taken as 3/2 or less commonly 9/4.
See also
Notes
- ↑ 1.0 1.1 The terms formal octave and pseudo-octave are often used specifically to designate a stretched or compressed octave, but they may more generally designate any kind of equave.
References
- ↑ Op de Coul, E.F. Scala help.
- ↑ ASCL Specification. Ableton.