Superpyth–22 equivalence continuum: Difference between revisions

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The '''superpyth-22 equivalence continuum''' is a continuum of 5-limit temperaments which equate a number of superpyth ~~commas~~, 20480/19683 = {{monzo| 12 -9 1 }}, with the 22-comma, {{monzo| 35 -22 }}. This continuum is theoretically interesting in that these are all 5-limit temperaments ~~supported~~ by [[22edo]].

The '''superpyth-22 equivalence continuum''' is a [[equivalence continuum|continuum]] of 5-limit [[regular temperament|temperaments]] which equate a number of [[superpyth comma]]s, 20480/19683 = {{monzo| 12 -9 1 }}, with the 22-comma, {{monzo| 35 -22 }}. This continuum is theoretically interesting in that these are all 5-limit temperaments [[support]]ed by [[22edo]].

All temperaments in the continuum satisfy (20480/19683)<sup>''n''</sup> ~ 250/243. Varying ''n'' results in different temperaments listed in the table below. It converges to 5-limit [[superpyth]] as ''n'' approaches infinity. If we allow non-integer and infinite ''n'', the continuum describes the set of all [[5-limit]] temperaments supported by [[22edo]] due to it being the unique equal temperament that tempers both commas and thus tempers all combinations of them. The just value of ''n'' is approximately 2.284531…, and temperaments having ''n'' near this value tend to be the most accurate ones.

All temperaments in the continuum satisfy (20480/19683)<sup>''n''</sup> ~ 250/243. Varying ''n'' results in different temperaments listed in the table below. It converges to 5-limit [[superpyth]] as ''n'' approaches infinity. If we allow non-integer and infinite ''n'', the continuum describes the set of all [[5-limit]] temperaments supported by 22edo due to it being the unique equal temperament that [[tempering out|tempers out]] both commas and thus tempers out all combinations of them. The just value of ''n'' is approximately 2.284531…, and temperaments having ''n'' near this value tend to be the most accurate ones.

The 22-comma is the characteristic 3-limit comma tempered out in 22edo, and has many advantages as a target. In each case, ''n'' equals the order of [[5/1|harmonic 5]] in the corresponding comma, and equals the number of steps to obtain the interval class of [[3/1|harmonic 3]] in the generator chain. For an ''n'' that is not coprime with 22, however, the corresponding temperament splits the [[octave]] into gcd (''n'', 22) parts, and splits the interval class of 3 into ''n''/gcd (''n'', 22). For example:

* [[Quasisuper]] (''n'' = 1) is generated by a fifth with an unsplit octave;

* [[Diaschismic]] (''n'' = 2) splits the octave in two, as 2 divides 22;

* [[Porcupine]] (''n'' = 3) splits the fourth in three, as 3 is coprime with 22;

* Etc.

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We may also invert the continuum by setting ''m'' such that 1/''m'' + 1/''n'' = 1. This may be called the ''quasisuper-22 equivalence continuum'', which is essentially the same thing. The just value of ''m'' is 1.778495…

We may also invert the continuum by setting ''m'' such that 1/''m'' + 1/''n'' = 1. This may be called the ''quasisuper-22 equivalence continuum'', which is essentially the same thing. The just value of ''m'' is 1.778495… The quasisuper comma is both larger and more complex than the superpyth comma. As such, this continuum does not contain as many useful temperaments, but still interesting nonetheless.

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-The '''superpyth-22 equivalence continuum''' is a continuum of 5-limit temperaments which equate a number of superpyth commas, 20480/19683 = {{monzo| 12 -9 1 }}, with the 22-comma, {{monzo| 35 -22 }}. This continuum is theoretically interesting in that these are all 5-limit temperaments supported by [[22edo]].
+The '''superpyth-22 equivalence continuum''' is a [[equivalence continuum|continuum]] of 5-limit [[regular temperament|temperaments]] which equate a number of [[superpyth comma]]s, 20480/19683 = {{monzo| 12 -9 1 }}, with the 22-comma, {{monzo| 35 -22 }}. This continuum is theoretically interesting in that these are all 5-limit temperaments [[support]]ed by [[22edo]].
-All temperaments in the continuum satisfy (20480/19683)<sup>''n''</sup> ~ 250/243. Varying ''n'' results in different temperaments listed in the table below. It converges to 5-limit [[superpyth]] as ''n'' approaches infinity. If we allow non-integer and infinite ''n'', the continuum describes the set of all [[5-limit]] temperaments supported by [[22edo]] due to it being the unique equal temperament that tempers both commas and thus tempers all combinations of them. The just value of ''n'' is approximately 2.284531…, and temperaments having ''n'' near this value tend to be the most accurate ones.
+All temperaments in the continuum satisfy (20480/19683)<sup>''n''</sup> ~ 250/243. Varying ''n'' results in different temperaments listed in the table below. It converges to 5-limit [[superpyth]] as ''n'' approaches infinity. If we allow non-integer and infinite ''n'', the continuum describes the set of all [[5-limit]] temperaments supported by 22edo due to it being the unique equal temperament that [[tempering out|tempers out]] both commas and thus tempers out all combinations of them. The just value of ''n'' is approximately 2.284531…, and temperaments having ''n'' near this value tend to be the most accurate ones.
+The 22-comma is the characteristic 3-limit comma tempered out in 22edo, and has many advantages as a target. In each case, ''n'' equals the order of [[5/1|harmonic 5]] in the corresponding comma, and equals the number of steps to obtain the interval class of [[3/1|harmonic 3]] in the generator chain. For an ''n'' that is not coprime with 22, however, the corresponding temperament splits the [[octave]] into gcd (''n'', 22) parts, and splits the interval class of 3 into ''n''/gcd (''n'', 22). For example:
+* [[Quasisuper]] (''n'' = 1) is generated by a fifth with an unsplit octave;
+* [[Diaschismic]] (''n'' = 2) splits the octave in two, as 2 divides 22;
+* [[Porcupine]] (''n'' = 3) splits the fourth in three, as 3 is coprime with 22;
+* Etc.
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 |}
-We may also invert the continuum by setting ''m'' such that 1/''m'' + 1/''n'' = 1. This may be called the ''quasisuper-22 equivalence continuum'', which is essentially the same thing. The just value of ''m'' is 1.778495…
+We may also invert the continuum by setting ''m'' such that 1/''m'' + 1/''n'' = 1. This may be called the ''quasisuper-22 equivalence continuum'', which is essentially the same thing. The just value of ''m'' is 1.778495… The quasisuper comma is both larger and more complex than the superpyth comma. As such, this continuum does not contain as many useful temperaments, but still interesting nonetheless.
 {| class="wikitable center-1"