Harmonic scale It was invented by Wendy Carlos and used on three pieces on her album "Beauty in the Beast" (1986): "Just Imaginings", "That's Just It", and "Yusae-Aisae". Versions of the scale have also been used by Ezra Sims and Frans Richter Herf. Though described by Carlos as containing "144 [= 12] distinct pitches to the octave", the twelve scales include 78 (= ) notes per octave. Technically there should then be duplicates and thus 57 (= 78 − 21) pitches (21 = ). For example, a perfect fifth above G (D) is the major tone above C. Harmonic scale The Harmonic
Tetratonic scale the note A occurs twice in this pattern, there are only four pitches in all. Tetratonic scale A tetratonic scale is a musical scale or mode with four notes per octave. This is in contrast to a heptatonic (seven-note) scale such as the major scale and minor scale, or a dodecatonic (chromatic 12-note ) scale, both common in modern Western music. Tetratonic scales are not common in modern art music, and are generally associated with prehistoric music. Tetratonic scales were common among the Plains Indians, though less common than the pentatonic scale. Amongst the Arapaho, Blackfoot, Crow, Omaha, Kiowa, Pawnee,