4L 3s

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↖ 3L 2s ↑ 4L 2s 5L 2s ↗
← 3L 3s 4L 3s 5L 3s →
↙ 3L 4s ↓ 4L 4s 5L 4s ↘
Scale structure
Step pattern LLsLsLs
sLsLsLL
Equave 2/1 (1200.0 ¢)
Period 2/1 (1200.0 ¢)
Generator size
Bright 5\7 to 3\4 (857.1 ¢ to 900.0 ¢)
Dark 1\4 to 2\7 (300.0 ¢ to 342.9 ¢)
TAMNAMS information
Name smitonic
Prefix smi-
Abbrev. smi
Related MOS scales
Parent 3L 1s
Sister 3L 4s
Daughters 7L 4s, 4L 7s
Neutralized 1L 6s
2-Flought 11L 3s, 4L 10s
Equal tunings
Equalized (L:s = 1:1) 5\7 (857.1 ¢)
Supersoft (L:s = 4:3) 18\25 (864.0 ¢)
Soft (L:s = 3:2) 13\18 (866.7 ¢)
Semisoft (L:s = 5:3) 21\29 (869.0 ¢)
Basic (L:s = 2:1) 8\11 (872.7 ¢)
Semihard (L:s = 5:2) 19\26 (876.9 ¢)
Hard (L:s = 3:1) 11\15 (880.0 ¢)
Superhard (L:s = 4:1) 14\19 (884.2 ¢)
Collapsed (L:s = 1:0) 3\4 (900.0 ¢)
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4L 3s refers to the structure of MOS scales with generators ranging from 1\4edo (one degree of 4edo, 300¢) to 2\7edo (two degrees of 7edo, or approx. 342.857¢). The name smitonic smy-TON-ik /smaɪˈtɒnɪk/ has been proposed (derived from the obsolete temperament name smite for sixix, from 'sharp minor third', taking sharp to mean sharp of the 12edo minor third).

4L 3s is a distorted diatonic, because it has one large step of diatonic (5L 2s, LLsLLLs) replaced with a small step (yielding LLsLsLs).

4L 3s has several temperament interpretations:

  1. With generator size between 5\18 (333.3c) and 11\39 (338.5c): Sixix, corresponding to a L/s ratio between 3/2 and 6/5.
  2. With generator size between 4\15 (320.0c) and 3\11 (327.3c): Orgone, corresponding to a L/s ratio between 3 and 2.
  3. With generator size between 5\19 (315.8c) and 4\15 (320.0c): Kleismic, corresponding to a L/s ratio between 4 and 3.

There are also other temperaments in the 4L 3s range, particularly amity and myna, but 7 notes in the generator chain are not enough to contain the most concordant chords in these temperaments; you would need to use a MODMOS or use a larger MOS gamut.

Notation

The notation used in this article is LsLsLsL = JKLMNOPJ unless specified otherwise. We denote raising and lowering by a chroma (L − s) by & "amp" and @ "at". (Mnemonics: & "and" means additional pitch. @ "at" rhymes with "flat".)

Thus the 11edo gamut is as follows:

J/Q& J&/K@ K/L@ L/K& L&/M@ M/N@ N/M& N&/O@ O/P@ P/O@ P&/J@ J

Scale tree

The spectrum looks like this:

Generator Tetrachord g in cents 2g 3g 4g Comments
1\4 1 0 1 300 600 900 0
9\35 8 1 8 308.571 617.143 925.714 34.286
8\31 7 1 7 309.677 619.355 929.023 38.71 Myna is around here
7\27 6 1 6 311.111 622.222 933.333 44.444
6\23 5 1 5 313.043 626.087 939.13 52.174
5\19 4 1 4 315.789 631.579 947.368 63.158 L/s = 4
9\34 7 2 7 317.647 634.294 951.941 70.588 Kleismic is around here
4\15 3 1 3 320 640 960 80 L/s = 3. Orgone starts here
11\41 8 3 8 321.951 643.902 965.854 87.805
29\108 21 8 21 322.222 644.444 966.667 88.889
18\67 13 5 13 322.388 644.776 967.364 89.522
7\26 5 2 5 323.077 646.154 969.231 92.308
31/115 22 9 22 323.478 646.956 970.434 93.913
2.44 1 2.44 323.501 647.002 970.003 94.004 Orgone minmax tuning
24/89 17 7 17 323.595 647.191 970.786 94.382
17/63 12 5 12 323.809 647.619 971.428 95.238
10/37 7 3 7 324.324 648.648 972.972 97.297
3\11 2 1 2 327.273 654.545 981.818 109.091 Boundary of propriety (generators
larger than this are proper) Orgone ends here.
8\29 5 3 5 331.034 662.069 993.013 124.138
21\76 13 8 13 331.579 663.158 994.739 126.316
34\123 21 13 21 331.707 663.415 995.122 126.829 Golden smitonic
13\47 8 5 8 331.915 663.83 995.745 127.66
5\18 3 2 3 333.333 666.667 1000 133.333 Optimum rank range (L/s=3/2)
Sixix
7\25 4 3 4 336 672 1008 144 Sixix
9\32 5 4 5 337.5 675 1012.5 150 Sixix
11\39 6 5 6 338.462 676.923 1015.385 153.846 Sixix
13\46 7 6 7 339.13 678.261 1017.391 156.522 (17/14)^3=9/5
15\53 8 7 8 339.623 679.245 1018.868 158.491 Amity is around here
2\7 1 1 1 342.857 685.714 1028.571 171.429

There are two notable harmonic entropy minima: kleismic, in which the generator is 6/5 and 6 of them make a 3/1, and myna, in which the generator is also 6/5 but now 10 of them make a 6/1 (so no 4/3's or 3/2's appear in this scale).

Tuning ranges

Sixix

Sixix tunings (with generator a supraminor third sharper than 5\18 and flatter than 9\32) have step ratios between 5/4 and 3/2.

Sixix can be considered "meantone smitonic". This is because sixix tunings share the following features with meantone diatonic tunings:

  • The large step is a "meantone", somewhere between near-10/9 (as in 32edo) and near-9/8 (as in 18edo). Thus sixix tempers out 81/80 like meantone does.
  • The major mosthird (made of two large steps) is a roughly meantone-sized major third, thus is a stand-in for the classical diatonic major third.

EDOs that support sixix include 18edo, 25edo, 32edo, and 43edo.

  • 18edo can be used to make large and small steps more distinct (the step ratio is 3/2, thus 18edo smitonic is distorted 19edo diatonic), or for its nearly pure 9/8. It also makes rising fifths (733.3c, a perfect mossixth) and falling fifths (666.7c, a major mosfifth) almost equally off from a just perfect fifth. 18edo is also more suited for conventionally jazz styles due to its 6-fold symmetry.
  • 25edo can be used for to make the major mosthird a good 5/4 (384¢).

The sizes of the generator, large step and small step of smitonic are as follows in various sixix tunings.

18edo 25edo Optimal (2.9.5 POTE) tuning
generator (g) 5\18, 333.33 7\25, 336.00 335.84
L (octave - 3g) 3\18, 200.00 4\25, 192.00 193.16
s (4g - octave) 2\18, 133.33 3\25, 144.00 143.36

Orgone

Orgone tunings (with generator a minor third sharper than 4\15 and flatter than 3\11) have step ratios between 2/1 and 3/1. It nominally approximates the 2.7.11 subgroup, on which the 26edo tuning is pretty much optimal. The large step approximates 8/7, and the major smifourth (2 large steps + 1 small step) approximates 11/8.

EDOs that support orgone include 11edo, 15edo, 26edo, and 37edo. The sizes of the generator, large step and small step of smitonic are as follows in various orgone tunings.

11edo 15edo 26edo JI intervals represented
generator (g) 3\11, 327.27 4\15, 320.00 7\26, 323.08 77/64
L (octave - 3g) 2\11, 218.18 3\15, 240.00 5\26, 230.77 8/7
s (4g - octave) 1\11, 109.09 1\15, 80.00 2\26, 92.31 128/121, (16/15)

Kleismic

Kleismic (aka hanson or keemun) tunings (with generator a minor third sharper than 5\19 and flatter than 4\15) have step ratios between 3/1 and 4/1. It is a 5-limit microtemperament. The generator is close to a 6/5, and 6 of them are used to reach 3/2; hence kleismic tempers out the kleisma 15625/15552.

EDOs that support kleismic include 15edo, 19edo, 34edo, 53edo, and 87edo.

The sizes of the generator, large step and small step of smitonic are as follows in various kleismic tunings.

15edo 19edo 34edo 2.3.5 POTE tuning JI intervals represented
generator (g) 4\15, 320.00 5\19, 315.79 7\26, 317.65 317.01 6/5
L (octave - 3g) 3\15, 240.00 4\19, 252.63 7\34, 247.06 248.98 15/13, 23/20
s (4g - octave) 1\15, 80.00 1\19, 63.16 2\34, 70.59 68.03 25/24

Intervals

Generators Notation (1/1 = J) Heptatonic interval category name Generators Notation of 2/1 inverse Heptatonic interval category name
The 7-note MOS has the following intervals (from some root):
0 J perfect unison 0 J octave
1 L perfect smithird -1 O perfect smisixth
2 N minor smififth (aka minor fifth) -2 M major smifourth (aka major fourth)
3 P minor smiseventh -3 K major smisecond
4 K@ minor smisecond -4 Q& major smiseventh
5 M@ minor smifourth (aka minor fourth) -5 N& major smififth (aka major fifth)
6 O@ diminished smisixth -6 L& augmented smithird
The chromatic 11-note MOS (either 7L 4s or 4L 7s) also has the following intervals (from some root):
7 J@ diminished octave -7 J& augmented unison
8 L@ diminished smithird -8 O& augmented smisixth
9 N@ diminished smififth -9 M& augmented smifourth
10 P@ diminished smiseventh -10 K& augmented smisecond

Modes

Pseudo-diatonic theory

Orgone

Sixix

Primodal theory

Primodal chords

Nejis

Rank-2 temperaments

Myna (27&31)

Kleismic (19&15, 2.3.5.7)

Orgone (15&11, 2.7.11)

Sixix (18&25)

Sixix can be viewed as a dual-fifth temperament, i.e. a temperament on the 2.3+.3-.5 "subgroup" (3+ = sharp 3, 3- = flat 3):

  • It has both a sharp fifth and a flat fifth but no near-just 3/2.
  • Combining the sharp fifth and the flat fifth yields a good approximation of 9/8; two 9/8's make a 5/4, so it tempers out 81/80 in the underlying 2.9.5 subgroup.
  • The chroma of sixix[7] is the difference between the sharp fifth and the flat fifth, and functions much like a(n untempered) comma in sixix harmony, giving two slightly different flavors of fifths, minor thirds, major thirds, etc, much like in porcupine harmony. Tempering out this comma leads to 7edo.

Samples

Sixix Fugue in 18edo (WIP)