2L 3s (3/2-equivalent)

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↖1L 2s⟨3/2⟩↑2L 2s⟨3/2⟩ 3L 2s⟨3/2⟩↗
←1L 3s⟨3/2⟩2L 3s⟨3/2⟩3L 3s⟨3/2⟩→
↙1L 4s⟨3/2⟩↓2L 4s⟨3/2⟩ 3L 4s⟨3/2⟩↘
Brightest mode LsLss
Period 3/2
Range for bright generator 2\5edf (280.8¢) to 1\2edf (351¢)
Range for dark generator 1\2edf (351¢) to 3\5edf (421.2¢)
Parent MOS 2L 1s⟨3/2⟩
Sister MOS 3L 2s⟨3/2⟩
Daughter MOSes 5L 2s⟨3/2⟩, 2L 5s⟨3/2⟩
Equal tunings
Supersoft (L:s = 4:3) 7\17edf (289¢)
Soft (L:s = 3:2) 5\12edf (292.5¢)
Semisoft (L:s = 5:3) 8\19edf (295.6¢)
Basic (L:s = 2:1) 3\7edf (300.8¢)
Semihard (L:s = 5:2) 7\16edf (307.1¢)
Hard (L:s = 3:1) 4\9edf (312¢)
Superhard (L:s = 4:1) 5\11edf (319.1¢)

2L 3s⟨3/2⟩, also called saturnian, is a non-octave moment of symmetry scale containing 2 large steps and 3 small steps, repeating every interval of 3/2 (701.955¢). Modes of this scale are rotations of the step pattern LsLss. Generators that produce this scale range from 280.782¢ to 350.978¢, or from 350.978¢ to 421.173¢.

Due to its minor third generator, this scale contains 2 diminished triads. Basic saturnian is in 7edf, an approximation of 12edo, which allows for playing regular music and saturnian music at the same time. 2L 3s〈3/2〉 is the parent of the 3/2-repeating microdiatonic scale, 5L 2s〈3/2〉, and the sister of 3L 2s〈3/2〉 (uranian) which is generated by a subminor third rather than a minor third.

Notation

The main way of notating the saturnian scale is using a 3/2-repeating notation consisting of 5 naturals. The notation used in this article is J Dionian is the JKLMN.

Intervals

Scale degree of 2L 3s⟨3/2⟩
Scale degree On J 7edf (Basic, L:s = 2:1) 9edf (Hard, L:s = 3:1) 12edf (Soft, L:s = 3:2) Approx. JI Ratios
Steps Cents Steps Cents Steps Cents
Perfect 0-mosdegree (unison) J 0 0 0 0 0 0 1/1 (exact)
Minor 1-mosdegree K 1 100.3 1 78 2 117
Major 1-mosdegree K& 2 200.6 3 234 3 175.5
Diminished 2-mosdegree L@ 2 200.6 2 156 4 234
Perfect 2-mosdegree L 3 300.8 4 312 5 292.5
Perfect 3-mosdegree M 4 401.1 5 390 7 409.5
Augmented 3-mosdegree M& 5 501.4 7 546 8 468
Minor 4-mosdegree N@ 5 501.4 6 468 9 526.5
Major 4-mosdegree N 6 601.7 8 624 10 585
Perfect 5-mosdegree (equave) J 7 702 9 702 12 702 3/2 (exact)

Genchain

-4 -3 -2 -1 0 1 2 3 4
d2ms m4ms m1ms P3ms P0ms P2ms M4ms M1ms A3ms

Theory

2L 3s〈3/2〉 can be interpreted as the nonoctave regular temperament named pythium by User:CompactStar, tempering out 81/80 in the 3/2.4.5 subgroup. This is the simplest 3/2-equivalent temperament not containing octaves. Because the 3/2-reduced 5th harmonic of 40/27 is conflated with the just perfect fifth, the CTE generator of this temperament is exactly the 32/27 Pythagorean minor third. The best extension of pythium to the 3/2.4.5.7 subgroup adds 64/63 to the comma list, making the CTE generator slightly flatter than 32/27, about 286 cents. Although the most accurate pythium generators are near 32/27, pythium can be tuned with minor thirds as sharp as that of 11edf's (319 cents).

Modes

The mode names are based on the 6 largest satellites of Saturn, excluding Titan since the "Titanian" name has been used for the uranian scale.

Modes of 2L 3s⟨3/2⟩
UDP Step pattern Mode names
4|0 LsLss Rhean
3|1 LssLs Iapetian
2|2 sLsLs Dionian
1|3 sLssL Tethyian
0|4 ssLsL Enceladean

Scale tree

Steps of ED Generator in cents Step ratio Comments
Bright Dark L:s Hardness
2\5edf 280.782 421.173 1:1 1 Equalized 2L 3s⟨3/2⟩
11\27edf 285.982 415.973 6:5 1.2
9\22edf 287.163 414.792 5:4 1.25 Optimal 3/2.4.5.7 pythium around here
16\39edf 287.982 413.973 9:7 1.286
7\17edf 289.04 412.915 4:3 1.333 Supersoft 2L 3s⟨3/2⟩
19\46edf 289.938 412.017 11:8 1.375
12\29edf 290.464 411.491 7:5 1.4
17\41edf 291.055 410.9 10:7 1.429
5\12edf 292.481 409.474 3:2 1.5 Soft 2L 3s⟨3/2⟩
18\43edf 293.842 408.113 11:7 1.571
13\31edf 294.368 407.587 8:5 1.6 Near-just 32/27, optimal 3/2.4.5 pythium around here
21\50edf 294.821 407.134 13:8 1.625
8\19edf 295.56 406.395 5:3 1.667 Semisoft 2L 3s⟨3/2⟩
19\45edf 296.381 405.574 12:7 1.714
11\26edf 296.981 404.974 7:4 1.75
14\33edf 297.799 404.156 9:5 1.8
3\7edf 300.838 401.117 2:1 2 Basic 2L 3s⟨3/2⟩
(Generators smaller than this are proper)
Augmented 8-mosstep is nearly an octave
13\30edf 304.181 397.775 9:4 2.25
10\23edf 305.198 396.757 7:3 2.333
17\39edf 305.98 395.975 12:5 2.4
7\16edf 307.105 394.85 5:2 2.5 Semihard 2L 3s⟨3/2⟩
18\41edf 308.175 393.78 13:5 2.6
11\25edf 308.86 393.095 8:3 2.667
15\34edf 309.686 392.269 11:4 2.75
4\9edf 311.98 389.975 3:1 3 Hard 2L 3s⟨3/2⟩
13\29edf 314.669 387.286 10:3 3.333
9\20edf 315.88 386.075 7:2 3.5
14\31edf 317.012 384.943 11:3 3.667
5\11edf 319.07 382.885 4:1 4 Superhard 2L 3s⟨3/2⟩
11\24edf 321.729 380.226 9:2 4.5
6\13edf 323.979 377.976 5:1 5
7\15edf 327.579 374.376 6:1 6
1\2edf 350.978 350.978 1:0 → ∞ Collapsed 2L 3s⟨3/2⟩
Degenerate scale with only 2 tones