Octatonic scale scale" . The twelve tones of the chromatic scale are covered by three disjoint diminished seventh chords. The notes from two such seventh-chords combination form an octatonic collection. Because there are three ways to select two from three, there are three octatonic scales in the twelve-tone system. Each octatonic scale has exactly two modes: the first begins its ascent with a whole step, while the second begins its ascent with a half step (semitone). These modes are sometimes referred to as the "whole step/half-step diminished scale" and the "half-step/whole step diminished scale", respectively. Each of the three distinct scales can
Major scale semitone (i.e. whole, whole, half). The major scale is maximally even. \override Score.TimeSignature #'stencil = ##f \relative c' { </score> The scale degrees are: \override Score.TimeSignature #'stencil = ##f </score> The triads built on each scale degree follow a distinct pattern. The roman numeral analysis is shown in parentheses. If a piece of music (or part of a piece of music) is in a major key, then the notes "in" the corresponding major scale are considered "diatonic" notes, while the notes "outside" the major scale are considered "chromatic" notes. Moreover, the key signature of the piece of music (or section)