In music, a synthetic scale is a scale which has been derived from a traditional diatonic major scale through the alteration of one degree by a semitone in either direction. Composer Ferruccio Busoni originally explored these scales in his A New Esthetic of Music and their number and variety were later clarified by J. Murray Barbour who also proposed the application of the procedure to scales of more or less than seven degrees, including pentatonic scales.
These synthetic pitch collections may serve as the basic melodic and/or harmonic material for a passage of music. However, the hundreds of available scales cause Murray Barbour to propose that, "the whole problem is of greater theoretical interest than of practical worth."
In C, the scale consists of the notes C, D, E, F#, A, B♭, C. The semitone steps for this scale are 2, 2, 2, 3, 1, 2. By adding a G to the scale, one would end up with the Lydian♭VII, the fourth degree of the Melodic Minor scale.
Scriabin's Mystic chord, when considered as the "Prometheus scale", is an example of a synthetic chord in that it is whole tone scale with one degree altered. However, it was not the generating element to Scriabin's music nor does his derivation of it from the whole tone scale necessarily indicate knowledge of Busoni's theories.
The pitches of synthetic scales may duplicate pre-existing scales though their derivation is different and their use is often quite different.
- Yamaguchi, Masaya. 2006. The Complete Thesaurus of Musical Scales, revised edition. New York: Masaya Music Services. ISBN 0-9676353-0-6.
- "Synthetic Musical Scales". Author(s): J. Murray Barbour. Source: The American Mathematical Monthly, Vol. 36, No. 3, (Mar., 1929), pp. 155-160.
- Busoni, Ferruccio (1907), translated Dr. Th. Baker (1911). Sketch Of A New Esthetic Of Music, p.29-39. ISBN 0-548-76595-2.