Diaschismic–gothmic equivalence continuum: Difference between revisions

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| [[Gammic]]
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| 95367431640625/95105071448064
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| {{monzo| -29 -11 20 }}
| {{monzo| -29 -11 20}}
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| [[Chlorine]]
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| [ [[Septendecima|very long]]; equal to ([[25/24]])<sup>17</sup> / [[2/1|2]] ]
| [ [[Septendecima|very long]]; equal to ([[25/24]])<sup>17</sup> / [[2/1|2]] ]
| {{monzo| -52 -17 34 }}
| {{monzo| -52 -17 34}}
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| [[Majvam]]
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| 2404631929946112/2384185791015625
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| {{monzo| 40 7 -22 }}
| {{monzo| 40 7 -22}}
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| [https://sintel.pythonanywhere.com/result?subgroup=2.3.5.13.17&reduce=on&weights=tenney&target=&edos=&commas=35184372088832%2F34332275390625%2C+289%2F288%2C+2197%2F2187&submit_comma=submit 34&142]
| [https://sintel.pythonanywhere.com/result?subgroup=2.3.5.13.17&reduce=on&weights=tenney&target=&edos=&commas=35184372088832%2F34332275390625%2C+289%2F288%2C+2197%2F2187&submit_comma=submit 34&142]
| 35184372088832/34332275390625
| 35184372088832/34332275390625
| {{monzo| 45 -2 18 }}
| {{monzo| 45 -2 -18}}
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Revision as of 17:50, 22 July 2024

The diaschismic-kleismic equivalence continuum is a continuum of 5-limit temperaments that describes the set of all 5-limit temperaments supported by 34edo.

A reasonable way of defining this continuum equates a number of diaschismas (2048/2025) with the Würschmidt comma (393216/390625), so that (2048/2025)n ~ 393216/390625. As a result, this may also be called the diaschismic-würschmidt equivalence continuum, or the diaschismic-gothic equivalence continuum, which is more or less the same thing. The just value of n is 0.5853…, and temperaments near this tend to be the most accurate. The gothic comma (134217728/129140163) is the characteristic 3-limit comma tempered out in 34edo, and it has a value of n = 4. Therefore, one can additionally define k = 4 - n, which has notable advantages - in particular, due to being determined in terms of the 3-limit comma and the comma with the next lowest power of 5, twice the numerator of the value of k represents the number of generator steps required to reach the 3rd harmonic while the denominator represents .

All temperaments in the continuum also satisfy (15625/15552)m ~ 393216/390625, for a value of m defined such that 1/n - 1/m = 1; equivalently, we can offset m by 1, and equate a number of kleismas (15625/15552) with the diaschisma, hence the name. Varying m results in different temperaments listed in the second table below. It converges to hanson as m approaches infinity, and is motivated by the fact that many important temperaments of 34edo follow a chain of commas connected by kleismas.

Temperaments in the diaschismic-gothic continuum
n k Temperament Comma
Ratio Monzo
4 0 Gothic 134217728/129140163 [27 -17
3 1 Immunity 1638400/1594323 [16 -13 2
2 2 Tetracot 20000/19683 [5 -9 4
3/2 5/2 Fifive 9765625/9565938 [-1 -14 10
1 3 Hanson/Kleismic 15625/15552 [-6 -5 6
2/3 10/3 Gammic 95367431640625/95105071448064 [-29 -11 20
3/5 17/5 Chlorine [ very long; equal to (25/24)17 / 2 ] [-52 -17 34
1/2 7/2 Vishnu 6115295232/6103515625 [23 6 -14
1/3 11/3 Majvam 2404631929946112/2384185791015625 [40 7 -22
0 4 Würschmidt 393216/390625 [17 1 -8
-1/2 9/2 34&142 35184372088832/34332275390625 [45 -2 -18
-1 5 Mabila 268435456/263671875 [28 -3 -10
-2 6 Goldis 549755813888/533935546875 [39 -7 -12
∞* Srutal 2048/2025 [11 -4 -2
* in projective tuning space, ∞ = -∞.

We may invert the continuum by setting m such that 1/n - 1/m = 1. The just value of m is 1.4117…, and temperaments near this tend to be the most accurate ones.

Temperaments with integer m in the kleismic-würschmidt continuum
m k Temperament Comma
Ratio Monzo
-4 8/3 34 & 113 152587890625/148769467776 [-7 -19 16
-3 5/2 Fifive 9765625/9565938 [-1 -14 10
-2 2 Tetracot 20000/19683 [5 -9 4
-1 Srutal 2048/2025 [11 -4 -2
0 4 Wurschmidt 393216/390625 [17 1 -8
1 7/2 Vishnu 6115295232/6103515625 [23 6 -14
2 10/3 Gammic 95367431640625/95105071448064 [-29 -11 20
3 13/4 Quatracot 1490116119384765625/1479074071160291328 [-35 -16 26
3 Hanson/Kleismic 15625/15552 [-6 -5 6
Temperaments with fractional m and n
Temperament m n k
Majvam 1/2 = 0.5 1/3 = 0.3 11/3 = 3.6
Chlorine 3/2 = 1.5 3/5 = 0.6 17/5 = 3.4
34&142 -1/3 = -0.3 -1/2 = -0.5 9/2 = 4.5