Hanson and cata

From Xenharmonic Wiki
(Redirected from Hanson)
Jump to navigation Jump to search
Kleismic; hanson; cata
Subgroups 2.3.5, 2.3.5.13
Comma basis 15625/15552 (2.3.5);
325/324, 625/624 (2.3.5.13)
Reduced mapping <1; 6 5 14]
Edo join 15 & 19
Generator (CTE) ~6/5 = 317.1c
MOS scales 3L 1s, 4L 3s, 4L 7s, 4L 11s, 15L 4s
Ploidacot alpha-hexacot
Minmax error (5-odd limit) 1.35c;
((2.3.5.13) 15-odd limit) 2.35c
Target scale size (5-odd limit) 15 notes;
((2.3.5.13) 15-odd limit) 34 notes
"Kleismic" redirects here. For the temperament families, see Kleismic family and Kleismic rank three family.

Kleismic, known in the 5-limit as either hanson or simply "kleismic", is a rank-2 temperament and parent of the kleismic family, characterized by the vanishing of the kleisma (15625/15552). It is generated by a classical minor third (6/5), six of which make a twelfth (3/1).

Another useful interpretation of the kleisma as a comma is that it makes the classical chromatic semitone, 25/24, into a third-tone by equating three of this interval to 9/8. As 9/8 = (25/24)(26/25)(27/26), it is natural to equate 25/24 to 26/25 and 27/26 as well, thereby tempering out the marveltwin comma (S25 × S26 = 325/324), and the tunbarsma (S25 = 625/624), resulting in a low-complexity but high-accuracy extension to the 2.3.5.13 subgroup, sometimes known as cata. As the chain of generators naturally gives us hemitwelfths at only 3 generator steps, this also corresponds directly to an interpretation of these as 26/15 (and thus hemifourths as 15/13) by tempering out S26 = 676/675.

Extensions with prime 7 include catakleismic (which adds 225/224, finding 7 at 22 generators up), countercata (which adds 5120/5103, finding 7 at 31 generators down), metakleismic (which adds 179200/177147, finding 7 at 56 generators up), keemun (which adds 49/48, finding 7 at 3 generators up), anakleismic (which adds 2240/2187, finding 7 at 37 generators up), and catalan (which adds 64/63, finding 7 at 12 generators down). Of these, catakleismic can perhaps be considered the canonical, as it makes a natural further equivalence of 25/24~26/25~27/26 to 28/27 and can be defined in the 7-limit by tempering out 225/224 and 4375/4374. However, countercata exists closer to the truly optimal range of kleismic (between 53edo and 87edo) and tempers out 4096/4095 where 65/64 and therefore 64/63 are close to just.

Most of these extensions can also incorporate prime 11 (and thereby reach the full 13-limit) by tempering out 385/384, equating the ~6/5 generator to 77/64, which works well since ~6/5 should be tuned sharp of just, bringing it closer to 77/64, which is in fact just at very close to 15edo's minor third of 320c.

For technical data, see Kleismic family #Hanson.

Interval chain

In the following table, odd harmonics 1–15 are labeled in bold.

# Cents* Approximate ratios
0 0.0 1/1
1 317.1 6/5, 65/54
2 634.2 13/9, 36/25
3 950.3 26/15, 45/26
4 68.4 25/24, 26/25, 27/26
5 385.6 5/4, 81/65
6 702.7 3/2
7 1019.8 9/5, 65/36
8 136.9 13/12, 27/25
9 454.0 13/10
10 771.1 25/16, 39/25, 81/52
11 1088.2 15/8
12 205.3 9/8
13 522.4 27/20, 65/48
14 839.6 13/8, 81/50
15 1156.7 39/20
16 273.8 75/64
17 590.9 45/32
18 908.0 27/16
19 25.1 65/64, 81/80

* In 2.3.5.13-subgroup CTE tuning

Tunings

Optimized tunings

Prime-optimized tunings
Weight-skew\Order Euclidean
Constrained Destretched
Tenney (2.3.5) CTE: ~6/5 = 317.0308¢ (2.3.5) POTE: ~6/5 = 317.007¢
Equilateral (2.3.5) CEE: ~6/5 = 317.1033¢

(11/61-kleisma)

Tenney (2.3.5.13) CTE: ~6/5 = 317.1110¢ (2.3.5.13) POTE: ~6/5 = 317.0756¢
DR and equal-beating tunings
Optimized chord Generator value Polynomial Further notes
3:4:5 (+1 +1) ~6/5 = 317.1496 g6 + 2g5 − 8 = 0 1–3–5 equal-beating tuning, close to 8/43-kleisma
4:5:6 (+1 +1) ~6/5 = 317.9593 g6 − 2g5 + 2 = 0 1–3–5 equal-beating tuning, close to 2/7-kleisma
10:12:15 (+2 +3) ~6/5 = 317.6675 g6 − 5g + 3 = 0 Close to 1/4-kleisma
9:13:15 (+2 +1) ~6/5 = 317.5679 3g3 + 4g − 10 = 0 Close to 13/36-marveltwin comma
13:15:18 (+2 +3) ~6/5 = 317.0010 3g3g − 4 = 0 Close to 13/51-marveltwin comma

Tuning spectrum

EDO
generator
Eigenmonzo
(unchanged interval)
*
Generator (¢) Comments
6/5 315.6413 Untempered tuning, lower bound of 5-odd-limit diamond tradeoff
5\19 315.7895 Lower bound of 2.3.5.13-subgroup 15-odd-limit diamond monotone
27/26 316.3343 1/4-tunbarsma
29\110 316.3636 110ff val
24\91 316.4835 91f val
27/25 316.6547 1/8-kleisma
19\72 316.6667
9/5 316.7995 1/7-kleisma
33\125 316.8000 125f val
26/25 316.9750 1/4-marveltwin comma
14\53 316.9811
3/2 316.9925 1/6-kleisma; 5- and 9-odd-limit minimax tuning
75/52 317.0274 1/2-tunbarsma
51\193 317.0984
15/8 317.1153 2/11-kleisma
88\333 317.1171
13/10 317.1349 13- and 15-odd-limit minimax tuning
37\140 317.1429
13/8 317.1805
60\227 317.1807
23\87 317.2414
5/4 317.2627 1/5-kleisma, upper bound of 5-odd-limit diamond tradeoff
13/12 317.3216
32\121 317.3554
41\155 317.4194
15/13 317.4197 1/3-marveltwin comma
9\34 317.6471
25/24 317.6681 1/4-kleisma, virtually DR 10:12:15
22\83 318.0723 83f val
13/9 318.3088 1/2-marveltwin comma, upper bound of 2.3.5.13-subgroup 15-odd-limit diamond tradeoff
125/72 318.3437 1/3-kleisma
13\49 318.3673 49f val
125/104 318.4135 Full tunbarsma
625/432 319.6949 1/2-kleisma
4\15 320.0000 Upper bound of 2.3.5.13-subgroup 15-odd-limit diamond monotone
65/54 320.9764 Full marveltwin comma

* Besides the octave

Other tunings

  • DKW (2.3.5): ~2 = 1\1, ~6/5 = 317.1983

Scales

Images

Kleismic.png

A chart of the tuning spectrum of hanson and cata, showing the offsets of odd harmonics 3, 5, 9, 13, and 15, as a function of the generator; all EDO tunings are shown with vertical lines whose length indicates the EDO's tolerance, i.e. half of its step size in either direction of just, and some small EDOs supporting the temperament are labeled. Comma fractions with corresponding eigenmonzos also labeled.

Music

Petr Pařízek
Chris Vaisvil

External links