Editing Generic and specific intervals (section)

[[Image:Maximal evenness seconds.png|thumb|The [[major scale]] is [[maximal evenness|maximally even]]. For example, for every generic interval of a second there are only two possible specific intervals: 1 semitone (a minor second) or 2 semitones (a major second).]]

In [[diatonic set theory]] a '''generic interval''' is the number of scale [[Step (music)|steps]] between [[note (music)|notes]] of a [[Set (music)|collection]] or [[scale (music)|scale]]. The largest generic [[interval (music)|interval]] is one less than the number of scale members. (Johnson 2003, p.&nbsp;26)

A '''specific interval''' is the clockwise distance between [[pitch class]]es on the [[chromatic circle]] ([[interval class]]), in other words the number of [[half step]]s between [[note (music)|notes]]. The largest specific [[interval (music)|interval]] is one less than the number of "chromatic" pitches. In twelve tone equal temperament the largest specific interval is 11. (Johnson 2003, p.&nbsp;26)

In the [[diatonic collection]] the generic interval is one less than the corresponding diatonic interval:
* Adjacent intervals, [[Major second|second]]s, are 1
* [[Major third|Third]]s = 2
* [[Perfect fourth|Fourth]]s = 3
* [[Perfect fifth|Fifth]]s = 4
* [[Major sixth|Sixth]]s = 5
* [[Major seventh|Seventh]]s = 6
The largest generic interval in the diatonic scale being 7 − 1 = 6.