Diaschismic–gothmic equivalence continuum: Difference between revisions

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table of fractional n also seems unnecessary, as they're either listed on the inversion table or down below
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The gothic comma is the characteristic [[3-limit]] comma tempered out in 34edo. Describing the continuum this way 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 ''n'' represents the number of generator steps required to reach the interval class of [[3/1|3]].
The gothic comma is the characteristic [[3-limit]] comma tempered out in 34edo. Describing the continuum this way 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 ''n'' represents the number of generator steps required to reach the interval class of [[3/1|3]].


Another reasonable way of defining this continuum equates a number of diaschismas with the [[393216/390625|würschmidt comma (393216/390625)]], so that (2048/2025)<sup>''k''</sup> ~ 393216/390625. As a result, ''k'' = 4 - ''n'', and this may also be called the ''diaschismic-würschmidt equivalence continuum'', which is more or less the same thing. The just value of ''k'' is 0.5853…, and temperaments near this tend to be the most accurate.  
Another reasonable way of defining this continuum equates a number of diaschismas with the [[393216/390625|würschmidt comma (393216/390625)]], so that (2048/2025)<sup>''k''</sup> ~ 393216/390625. As a result, ''k'' = 4 - ''n'', and this labeling may also be called the ''diaschismic-würschmidt equivalence continuum''. The just value of ''k'' is 0.5853…, and temperaments near this tend to be the most accurate.  


{| class="wikitable center-1 center-2"
{| class="wikitable center-1 center-2"

Revision as of 23:34, 23 July 2024

The diaschismic-gothic equivalence continuum, also referrable as the diaschismic-würschmidt equivalence continuum, diaschismic-kleismic equivalence continuum, or kleismic-würschmidt equivalence continuum, is a continuum of 5-limit temperaments that describes the set of all 5-limit temperaments supported by 34edo.

All temperaments in the continuum satisfy (2048/2025)n ~ [27 -17, equating a number of diaschismas (2048/2025) with the gothic comma. Varying n results in different temperaments listed in the table below. It converges to diaschismic as n approaches infinity. If we allow non-integer and infinite n, the continuum describes the set of all 5-limit temperaments supported by 34edo due to it being the unique equal temperament that tempers out both commas and thus tempers out all combinations of them. The just value of n is approximately 3.41464…, and temperaments having n near this value tend to be the most accurate ones.

The gothic comma is the characteristic 3-limit comma tempered out in 34edo. Describing the continuum this way 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 n represents the number of generator steps required to reach the interval class of 3.

Another reasonable way of defining this continuum equates a number of diaschismas with the würschmidt comma (393216/390625), so that (2048/2025)k ~ 393216/390625. As a result, k = 4 - n, and this labeling may also be called the diaschismic-würschmidt equivalence continuum. The just value of k is 0.5853…, and temperaments near this tend to be the most accurate.

Temperaments with integer n and k
k n 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
1 3 Hanson 15625/15552 [-6 -5 6
0 4 Würschmidt 393216/390625 [17 1 -8
-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, ∞ = -∞.

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

Temperaments with integer s in the kleismic-würschmidt continuum
s Temperament Comma
Ratio Monzo
-4 34 & 113 152587890625/148769467776 [-7 -19 16
-3 Fifive 9765625/9565938 [-1 -14 10
-2 Tetracot 20000/19683 [5 -9 4
-1 Srutal 2048/2025 [11 -4 -2
0 Würschmidt 393216/390625 [17 1 -8
1 Vishnu 6115295232/6103515625 [23 6 -14
2 Gammic (28 digits) [-29 -11 20
3 Quatracot (38 digits) [-35 -16 26
Hanson 15625/15552 [-6 -5 6
Temperaments with fractional k and s
s k n Temperament Comma
1/2 = 0.5 1/3 = 0.3 11/3 = 3.6 Majvam [40 7 -22
3/2 = 1.5 3/5 = 0.6 17/5 = 3.4 Chlorine [-52 -17 34
-1/3 = -0.3 -1/2 = -0.5 9/2 = 4.5 34 & 142 [45 -2 -18