A hexatonic scale is a musical scale with six pitches or notes per octave. Famous examples include the whole tone scale, C D E F# G# A# C; the augmented scale, C D# E G Ab B C; the Prometheus scale, C D E F# A Bb C; and what some jazz theory calls the "blues scale", C Eb F F# G Bb C.

Whole-tone scale

The whole-tone scale is a series of whole-tones. It has two non-enharmonically equivalent positions: C D E F# G# A# C and Db Eb F G A B Db. It is primarily associated with the French impressionist composer Claude Debussy, who used it in such pieces of his as Voiles and La vent dans la plaine, both from his first book of piano Preludes.

This whole-tone scale has appeared occasionally and sporadically in jazz at least since Bix Beiderbecke's impressionistic piano piece "In a Mist". Bop pianist Thelonius Monk often interpolated whole-tone scale flourishes into his improvisations and compositions.

Augmented scale

The augmented scale is so called because it can be thought of as an interlocking combination of two augmented triads a minor second or minor third apart: C E G# and Eb G B. It made one of its most celebrated early appearances in Franz Liszt's Faust Symphony (Eine Faust Symphonie).

Prometheus scale

The Prometheus scale is so called because of its prominent use in Alexander Scriabin's symphonic poem Prometheus: The Poem of Fire. Scriabin himself called this set of pitches, voiced as the simultaneity (in ascending order) C F# Bb E A D the "mystic chord". Others have referred to it as the "Promethean chord". It is likely that Scriabin was the first composer ever to use this scale for whole passages of music - as against its accidental transient occurrence resulting from passing chromatic harmony, which did occur earlier in various composers' music, even occasionally as early as Beethoven. Probably 90 percent or more of Prometheus is composed in the Prometheus scale, at one pitch or another (the transposition of the scale at any given time usually changing every few bars).

Blues scale

Since blues notes (or blue notes) are alternate inflections, strictly speaking there can be no one blues scale, but the scale most commonly called "the blues scale" comprises a flatted seventh blues note, a flatted third blues note, a flatted fifth blues note, and the flatted fifth's note of upward resolution along with other pitches derived from the minor pentatonic scale, C Eb F F# G Bb C.