By Evenness
Scales
Cluster-free, 7 Notes
7-34, (013468t), Acoustic
Set Class
In Harmonious, the acoustic scale or melodic minor scale refers to the heptatonic (seven-note) set class, the unordered collection of notes with seven modes, including the Lydian Dominant (Acoustic) and Melodic Minor modes.
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See also Acoustics for the physics behind the acoustic aspect of the acoustic scale.
The scale is very even, symmetric and related to transpositions of the diatonic scale by short voice leadings. See Beyond Diatonic for more on the set class for this scale. Each transposition of the acoustic scale is a semitone voice-leading step away from two transpositions of the diatonic scale, and a step from one harmonic minor scale, and a step from one harmonic major scale. It is also related to the whole-tone scale by short voice leadings.
The melodic minor scale is traditionally thought of as a natural minor scale modified by two sharps (on the sixth and seventh scale degrees), or a harmonic minor scale with an extra sharp on the sixth scale degree (when thought of as an OTC-equivalent object).
the minimum Euclidean distance from this set to any transposition of the perfectly even 7 note chord, in semitones