User:Moremajorthanmajor/7L 3s (perfect eleventh-equivalent)

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7L 3s<perfect eleventh> (sometimes called Bolivar or Choralic) refers to a non-octave MOS scale family with a period of a perfect eleventh and which has 7 large and 3 small steps. These scales are the sister of diaquadic with the melodic spacing of diatonic scales. A pathological trait these scales exhibit is that normalization to edo collapses the range for the bright generator to the octave.

Modes

The modes contain fundamental chords with notes such that they convert a tritone substitution into a diatonic chord substitution.

  • LLLsLLsLLs 9|0 (Lydian ♮11)
  • LLsLLLsLLs 8|1 (Major, Ionian)
  • LLsLLsLLLs 7|2 (Mixolydian)
  • LLsLLsLLsL 6|3 (Mahur)
  • LsLLLsLLsL 5|4 (Dorian)
  • LsLLsLLLsL 4|5 (Minor, Aeolian)
  • LsLLsLLsLL 3|6 (Aeolian b9)
  • sLLLsLLsLL 2|7 (Phrygian)
  • sLLsLLLsLL 1|8 (Locrian)
  • sLLsLLsLLL 0|9 (Locrian b8)

Intervals

The generator (g) will fall between 480 cents (2\5 - two degrees of 5edo) and 514 cents (2\5 - two degrees of 5edo), hence a perfect fourth.

2g, then, will fall between 960 cents (4\5) and 1029 cents (6\7), the range of minor sevenths.

The "large step" will fall between 171 cents (1\7) and 240 cents (1\5), the range of major seconds.

The "small step" will fall between 0 cents and 171 cents, sometimes sounding like a submajor second, and sometimes sounding like a quartertone or smaller microtone.

# generators up Notation (1/1 = 0) name In L's and s's # generators up Notation of eleventh inverse name In L's and s's
The 10-note MOS has the following intervals (from some root):
0 0 perfect unison 0 0 0 perfect eleventh 7L+3s
1 7 perfect octave 5L+2s -1 3 perfect fourth 2L+1s
2 4 just fifth 3L+1s -2 6 minor seventh 4L+2s
3 1 major second 1L -3 9v minor tenth 6L+3s
4 8 major ninth 6L+2s -4 2v minor third 1L+1s
5 5 major sixth 4L+1s -5 5v minor sixth 3L+2s
6 2 major third 2L -6 8v minor ninth 5L+3s
7 9 major tenth 7L+2s -7 1v minor second 1s
8 6^ major seventh 5L+1s -8 4v diminished fifth 2L+2s
9 3^ augmented fourth 3L -9 7v diminished octave 4L+3s
10 0^ augmented unison 1L-1s -10 0v diminished eleventh 6L+4s
The chromatic 17-note MOS (either 7L 10s, 10L 7s, or 17edXI) also has the following intervals (from some root):
11 7^ augmented octave 6L+1s -11 3v diminished fourth 1L+2s
12 4^ augmented fifth 4L -12 6v diminished seventh 3L+3s
13 1^ augmented second 2L-1s -13 9w diminished tenth 5L+4s
14 8^ augmented ninth 7L+1s -14 2w diminished third 2s
15 5^ augmented sixth 5L -15 5w diminished sixth 2L+3s
16 2^ augmented third 3L-1s -16 8w diminished ninth 4L+4s
# generators up Notation (1/1 = G ut, ~8/3 = C sol fa ut) name In L's and s's # generators up Notation of twenty-first inverse name In L's and s's
The 20-note MOS has the following intervals (from some root):
0 G ut, C sol fa ut perfect unison, perfect eleventh 0, 7L+3s 0 G ut, C sol fa ut perfect eleventh, “perfect” minor twenty-first 7L+3s, 14L+6s
1 G sol fa re ut, C fa perfect octave, perfect eighteenth 5L+2s, 12L+5s -1 C fa ut, F fa ut perfect fourth, minor fourteenth 2L+1s, 9L+4s
2 D sol re ut, G sol fa ut just fifth, perfect fifteenth 3L+1s, 10L+4s -2 F fa ut, B fa minor seventh, minor seventeenth 4L+2s, 11L+5s
3 A re, D sol la re ut major second, perfect twelfth 1L, 8L+3s -3 B fab, E lab minor tenth, minor twentieth 6L+3s, 13L+6s
4 A la sol re mi, D sol major ninth, perfect nineteenth 6L+2s, 13L+5s -4 B mib, E la mi reb minor third, minor thirteenth 1L+1s, 8L+4s
5 E la mi re, A la sol re major sixth, major sixteenth 4L+1s, 11L+4s -5 E la mi reb, A la mi reb minor sixth, minor sixteenth 3L+2s, 10L+5s
6 B mi, E la mi re si major third, major thirteenth 2L, 9L+3s -6 A la sol reb, D solb minor ninth, diminished nineteenth 5L+3s, 12L+6s
7 B si la mi, E la major tenth, major twentieth 7L+2s, 14L+5s -7 A reb, D sol la reb minor second, diminished twelfth 1s, 7L+4s
8 F si mi, B si la mi major seventh, major seventeenth 5L+1s, 12L+4s -8 D sol re utb, G sol fa utb diminished fifth, diminished fifteenth 2L+2s, 9L+5s
9 C si, F si mi augmented fourth, major fourteenth 3L, 10L+3s -9 G sol fa utb, C fab diminished octave, diminished eighteenth 4L+3s, 11L+6s
10 G ut#, C si augmented unison, augmented eleventh 1L-1s, 8L+2s -10 G utb, C fa utb diminished eleventh, diminished twenty-first 6L+4s, 13L+7s
The chromatic 17-note MOS (either 14L 20s, 20L 14s, or 34edXXI) also has the following intervals (from some root):
11 G sol re ut#, C si augmented octave, augmented eighteenth 6L+1s, 13L+4s -11 C fa utb, F fa utb diminished fourth, diminished fourteenth 1L+2s,

8L+5s

12 D sol re ut#, G sol fa ut# augmented fifth, augmented fifteenth 4L, 11L+3s -12 F fa utb, B fab diminished seventh, diminished seventeeth 3L+3s, 10L+6s
13 A re#, D sol re ut# augmented second, augmented twelfth 2L-1s, 9L+2s -13 B fab, E labb diminished tenth, diminished twentieth 5L+4s, 12L+7s
14 A la sol re mi#, D sol# augmented ninth, augmented nineteenth 7L+1s, 14L+4s -14 B mibb, E la mi re sibb diminished third, diminished thirteenth 2s, 7L+5s
15 E la mi re#, A la sol re# augmented sixth, augmented sixteenth 5L, 12L 3s -15 E la mi rebb, A la sol rebb diminished sixth, diminished sixteenth 2L+3s, 9L+6s
16 B mi#, E la mi re si# augmented third, augmented thirteenth 3L-1s,

10L+2s

-16 A sol la mi rebb, D la solbb diminished ninth, doubly diminished nineteenth 4L+4s, 11L+7s

Scale tree

The generator range reflects two extremes: one where L = s (3\10), and another where s = 0 (2\7). Between these extremes, there is an infinite continuum of possible generator sizes. By taking freshman sums of the two edges (adding the numerators, then adding the denominators), we can fill in this continuum with compatible ~ed8/3s, increasing in number of tones as we continue filling in the in-betweens. Thus, the smallest in-between ~ed8/3 would be (3+2)\(10+7) = 5\17 – five degrees of 17edXI:

Generator Cents L s L/s Comments
7\10 514.286 1 1 1.000
40\57 510.000 6 5 1.200
33\47 509.091 5 4 1.250
59\84 508.475 9 7 1.286
26\37 507.692 4 3 1.333
45\64 506.667 7 5 1.400
19\27 505.263 3 2 1.500 L/s = 3/2
50\71 504.000 8 5 1.600
31\44 503.226 5 3 1.667
43\61 502.326 7 4 1.750
55\78 501.818 9 5 1.800
12\17 500.000 2 1 2.000 Basic Bolivar

(Generators smaller than this are proper)

101\143 499.010 17 8 2.125
89\126 498.876 15 7 2.143
77\109 498.701 13 6 2.167
65\92 498.452 11 5 2.200
53\75 498.113 9 4 2.250
41\58 497.561 7 3 2.333
29\41 496.552 5 2 2.500
46\65 495.652 8 3 2.667
17\24 494.118 3 1 3.000 L/s = 3/1
73\103 493.151 13 4 3.250
56\79 492.857 10 3 3.333
39\55 492.308 7 2 3.500
61\86 491.803 11 3 3.667
22\31 490.909 4 1 4.000
49\69 489.796 9 2 4.500
27\38 488.889 5 1 5.000
32\45 487.500 6 1 6.000
5\7 480.000 1 0 → inf

The scale produced by stacks of 5\17 is the 12edo diatonic scale.

Other compatible ~ed8/3s include: ~37ed8/3, ~27ed8/3, ~44ed8/3, ~41ed8/3, ~24ed8/3, ~31ed8/3.

You can also build this scale by equally dividing frequency ratio 8:3 which is not a member of an edo or stacking frequency ratio 4:3 which is not a member of an equal division of it within it.

Rank-2 temperaments

The Bolivar rank-2 temperament spells its major tetrad 4:5:6:8 or 14:18:21:28root-3(2g-p)-(2g-p)-(1g) (p = 8/3, g = 2/1) and its minor tetrad 6:7:9:12 or 10:12:15:20 root-2(p-2g)-(2g-p)-(1g) (p = 8/3, g = 2/1). Basic 17ed8/3 fits both interpretations.

Bolivar-Meantone

Subgroup: 8/3.2.5/4

Comma list: 81/80

POL2 generator: ~2/1 = 1196.3254

Mapping: [1 0 -3], 0 1 6]]

Optimal ET sequence: 17ed8/3, 27ed8/3, 44ed8/3

Bolivar-Superpyth

Subgroup: 8/3.2.7/6

Comma list: 64/63

POL2 generator: ~2/1 = 1206.6167

Mapping: [1 0 2], 0 1 -4]]

Optimal ET sequence: 17ed8/3, 24ed8/3, 31ed8/3, 38ed8/3

7-note subsets

If you stop the chain at 7 tones, you have a heptatonic scale of the form 3L 4s:

L s s L s L s

The large steps here consist of L+s of the 10-tone system, and the small step is the same as L.

Tetrachordal structure

Due to the frequency of perfect fourths and fifths in this scale, it can also be analyzed as a tetrachordal scale.

See also

7L 3s (8/3-equivalent) - idealized tuning

14L 6s (7/1-equivalent) - Guidotonic dominant Archytas tuning

14L 6s (78/11-equivalent) - Guidotonic dominant Neogothic tuning

14L 6s (36/5-equivalent) - Guidotonic dominant Meantone tuning