User:Inthar/MV3: Difference between revisions
this isnt mv3 Tags: Mobile edit Mobile web edit |
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L = Y'Z, M = X, S = Z | L = Y'Z, M = X, S = Z | ||
=== "Diacot" === | <!--=== "Diacot" === | ||
5-limit MV3 detempering of dicot[10]: 81/80 10/9 16/15 10/9 81/80 10/9 16/15 10/9 81/80 (found by ks26), SLMLSLMLS | 5-limit MV3 detempering of dicot[10]: 81/80 10/9 16/15 10/9 81/80 10/9 16/15 10/9 81/80 (found by ks26), SLMLSLMLS | ||
S LM LS LM LS | S LM LS LM LS | ||
SL ML SL ML S | SL ML SL ML S--> | ||
== MV3 proof == | == MV3 proof == | ||
Prove the following: "It is a mathematical fact that, with only one exception, at least two of the three steps must occur the same number of times. For example, it is possible to have a max-variety-3 scale with 3 small steps, 5 medium steps, and 3 large steps, because there are the same number of small steps as large steps. But a max-variety-3 scale with 3 small steps, 5 medium steps, and 4 large steps is impossible. (The one exception to this rule is "aabacab", along with its repetitions "aabacabaabacab", etc.) Because of this, there always exists some "generator" interval for any max-variety-3 scale (other than the one exception) such that the scale can be expressed as two parallel chains of this generator which are almost equal in length (the lengths are either equal, or differ by 1). Once you have chosen a rank-3 temperament and a specific generator interval, there is a mechanical procedure to generate all max-variety-3 scales of a certain size (of which there are, however, infinitely many)." | Prove the following: "It is a mathematical fact that, with only one exception, at least two of the three steps must occur the same number of times. For example, it is possible to have a max-variety-3 scale with 3 small steps, 5 medium steps, and 3 large steps, because there are the same number of small steps as large steps. But a max-variety-3 scale with 3 small steps, 5 medium steps, and 4 large steps is impossible. (The one exception to this rule is "aabacab", along with its repetitions "aabacabaabacab", etc.) Because of this, there always exists some "generator" interval for any max-variety-3 scale (other than the one exception) such that the scale can be expressed as two parallel chains of this generator which are almost equal in length (the lengths are either equal, or differ by 1). Once you have chosen a rank-3 temperament and a specific generator interval, there is a mechanical procedure to generate all max-variety-3 scales of a certain size (of which there are, however, infinitely many)." | ||
Claim: A MV3 scale always has some subset (made by combining some of the two-step intervals into one) that is also MV3. | Claim: A MV3 scale always has some subset (made by combining some of the two-step intervals into one) that is also MV3. | ||