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
Scale (music) pitches. A common scale in Eastern music is the pentatonic scale, which consists of five notes that span an octave. Some scales span part of an octave; Several such short scales are typically combined to form a scale spanning a full octave or more, and usually called with a third name of its own. The Middle Eastern music has around a dozen such basic short scales that are combined to form hundreds of full-octave spanning scales. Among these middle eastern scales Hejaz scale has one scale step spanning 14 intervals (of the middle eastern type found 53 in an octave)