Brief explanation of musical intervals, what they are and how are they called.
An interval is the difference in pitch between two sounds 1 and most commonly differences between notes.
The smallest of these intervals is a semitone
An interval is named according to its
- quality and
- also called diatonic number (the intervals formed by the notes of a diatonic scale are called diatonic)
For example, minor third (or m3) is an interval name, in which the term:
- minor (m) describes the quality of the interval, and
- third (3) indicates its number.
The name of any interval is further qualified using the terms:
- perfect (P),
- called like this because they were traditionally considered perfectly consonant
- major (M),
- minor (m),
- augmented (A),
- intervals which are wider by one semitone than perfect or major intervals, while having the same interval number
- diminished (d)
- intervals which are narrower by one semitone than perfect or major intervals, while having the same interval number
The number of an interval is the number of letter names it encompasses. Numbers can be:
Prout, Ebenezer (1903), “I-Introduction”, Harmony, Its Theory and Practice (30th edition, revised and largely rewritten ed.), London: Augener; Boston: Boston Music Co., p. 1, ↩︎