Chord cubes

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A cube scale is a 7-limit scale (we might also consider the 9 odd limit) whose notes are derived from a cube in the 7-limit lattice of chords. For odd n, we will call the octave-reduced set of notes deriving from all chords of the form [i, j, k], (1-n)/2 ≤ i, j, k ≤ (n-1)/2, Cube(n). If n is even, we will use Cube(n) to refer to the notes of [i, j, k] with (2-n)/2 ≤ i, j, k < n/2. If n is odd, Cube(n) has (n+1)^3/2 notes to it; if n is even, its growth is more complicated but still approximately cubic. There are however two types of chord cubes for each n; for even n, we define the alternative cube Alt(n) via -n/2 ≤ i, j, k ≤ (n-2)/2, and for odd n, Alt(n), (1-n)/2 ≤ i+1, j, k ≤ (n-1)/2.

Here are the smaller cube scales:

Cube(2) -- the stellated hexany, 14 notes

[21/20, 15/14, 35/32, 9/8, 5/4, 21/16, 35/24, 3/2, 49/32, 25/16, 105/64, 7/4, 15/8, 2]

Alt(2) -- the 7-limit tonality diamond, 13 notes

[8/7, 7/6, 6/5, 5/4, 4/3, 7/5, 10/7, 3/2, 8/5, 5/3, 12/7, 7/4, 2]

Cube(3) 32 notes

[49/48, 25/24, 21/20, 15/14, 35/32, 9/8, 8/7, 7/6, 6/5, 60/49, 49/40, 5/4, 9/7, 21/16, 4/3, 7/5, 10/7, 35/24, 3/2, 49/32, 25/16, 8/5, 105/64, 5/3, 42/25, 12/7, 7/4, 25/14, 9/5, 15/8, 35/18, 2]

Alt(3) 32 notes

[36/35, 21/20, 15/14, 9/8, 8/7, 7/6, 6/5, 60/49, 49/40, 5/4, 9/7, 21/16, 4/3, 48/35, 7/5, 10/7, 36/25, 72/49, 3/2, 54/35, 8/5, 5/3, 42/25, 12/7, 7/4, 25/14, 9/5, 64/35, 15/8, 48/25, 96/49, 2]

Cube(4) 62 notes

[49/48, 525/512, 25/24, 21/20, 15/14, 343/320, 35/32, 125/112, 9/8, 8/7, 147/128, 7/6, 75/64, 6/5, 175/144, 60/49, 49/40, 315/256, 5/4, 63/50, 245/192, 9/7, 125/96, 21/16, 4/3, 75/56, 343/256, 27/20, 175/128, 7/5, 45/32, 10/7, 735/512, 35/24, 147/100, 3/2, 75/49, 49/32, 25/16, 63/40, 8/5, 45/28, 105/64, 5/3, 42/25, 27/16, 245/144, 12/7, 7/4, 25/14, 343/192, 9/5, 175/96, 90/49, 147/80, 15/8, 245/128, 27/14, 35/18, 125/64, 63/32, 2]

Alt(4) 63 notes

[50/49, 49/48, 36/35, 25/24, 21/20, 16/15, 15/14, 35/32, 10/9, 28/25, 9/8, 8/7, 7/6, 25/21, 6/5, 128/105, 60/49, 49/40, 5/4, 32/25, 9/7, 35/27, 64/49, 21/16, 4/3, 168/125, 49/36, 48/35, 25/18, 480/343, 7/5, 10/7, 343/240, 36/25, 35/24, 72/49, 125/84, 3/2, 32/21, 49/32, 54/35, 14/9, 25/16, 8/5, 80/49, 49/30, 105/64, 5/3, 42/25, 12/7, 7/4, 16/9, 25/14, 9/5, 64/35, 28/15, 15/8, 40/21,

48/25, 35/18, 96/49, 49/25, 2]

Scales

cube3

cube4

Scales tempered in 3600et

cube3enn

cube4enn