Kleismic family: Difference between revisions
m →Subgroup extensions: extension to prime 37 is opportunistic (only crudely fits the fact that we have a semifourth present; 37 is complex) while the extension to prime 41 is natural for any temp with an accurate but slightly flat 5, so can be noted in kleismic |
m →2.3.5.13: note prime 41 |
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[[Badness]] (Sintel): 0.310 | [[Badness]] (Sintel): 0.310 | ||
=== 2.3.5.13 === | === 2.3.5.13 === | ||
Kleismic lends itself to a natural extension to the [[2.3.5.13 subgroup]], as the hemitwelfth, reached by three generator steps, can be interpreted as [[26/15]]. The structure of the temperament as dividing 3/1 into 6 equal parts can be deduced completely from its [[S-expression]]-based comma list of {{nowrap| {[[325/324|S10/S12 = S25⋅S26]], ([[625/624|S25]],) [[676/675|S13/S15 = S26]]} }}. Specifically, dividing 3/1 into two halves of ~26/15 is equivalent to dividing 4/3 into two halves of ~15/13, hence the [[semiparticular]] S13/S15 = ([[4/3|16/12]])/([[15/13]])<sup>2</sup>. From here, we notice that (26/15)/(13/9) = 6/5, so all that remains is dividing 13/9 into two 6/5's via the semiparticular S10/S12 = (13/9)/([[6/5|12/10]])<sup>2</sup>, hence explaining the mapping of the entire 2.3.5.13 subgroup. This temperament has historically been called cata. (For a version of cata with a 1\5 period, see [[thunderclysmic]].) | Kleismic lends itself to a natural extension to the [[2.3.5.13 subgroup]], as the hemitwelfth, reached by three generator steps, can be interpreted as [[26/15]]. The structure of the temperament as dividing 3/1 into 6 equal parts can be deduced completely from its [[S-expression]]-based comma list of {{nowrap| {[[325/324|S10/S12 = S25⋅S26]], ([[625/624|S25]],) [[676/675|S13/S15 = S26]]} }}. Specifically, dividing 3/1 into two halves of ~26/15 is equivalent to dividing 4/3 into two halves of ~15/13, hence the [[semiparticular]] S13/S15 = ([[4/3|16/12]])/([[15/13]])<sup>2</sup>. From here, we notice that (26/15)/(13/9) = 6/5, so all that remains is dividing 13/9 into two 6/5's via the semiparticular S10/S12 = (13/9)/([[6/5|12/10]])<sup>2</sup>, hence explaining the mapping of the entire 2.3.5.13 subgroup. This temperament has historically been called cata. Note that the accuracy of it as providing a slightly flat 5/4 in ideal tunings lends a possible (but complex) extension to prime 41 via 32/25~41/32 (via [[1025/1024]]). (For a version of cata with a 1\5 period, see [[thunderclysmic]].) | ||
Subgroup: 2.3.5.13 | Subgroup: 2.3.5.13 | ||