TOP tuning: Difference between revisions
started rework (some header shifting, val, monzo template introducetion). I finally gave up because the math extension seems to fit better on pages like this |
Cmloegcmluin (talk | contribs) →TOP with "inconsistent" rational tuning extensions: link to tuning map |
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Note that there is no mapping for 3 which would map 9/1 to 51 steps, since 51 is an odd number, so it is useful to have both mappings: the regular 9/1, for use in chords such as the "[[Mavila]]" major 9 chord of 0-375-675-1050-1350, so that the 1350 cent 9/4 is a stack of two ~675 cent 3/2's, and the tempered 4:7:9 at 0-975-1425, which need not have any 3/2 at all. | Note that there is no mapping for 3 which would map 9/1 to 51 steps, since 51 is an odd number, so it is useful to have both mappings: the regular 9/1, for use in chords such as the "[[Mavila]]" major 9 chord of 0-375-675-1050-1350, so that the 1350 cent 9/4 is a stack of two ~675 cent 3/2's, and the tempered 4:7:9 at 0-975-1425, which need not have any 3/2 at all. | ||
It so happens that for some full prime-limit temperaments, the TOP tuning remains optimal even if we use "inconsistent" mappings for any composite rational - or even ''every'' rational - as long as we are willing to go with the restriction that such mappings only be used if they are tuned better than the regular consistent ones. We will call tuning | It so happens that for some full prime-limit temperaments, the TOP tuning remains optimal even if we use "inconsistent" mappings for any composite rational - or even ''every'' rational - as long as we are willing to go with the restriction that such mappings only be used if they are tuned better than the regular consistent ones. We will call [[tuning map]]s that obey this restriction '''admissible.''' | ||
As an example, if our tuning map has the "consistent" 9/8 tuned to 204, but where we have an extra "inconsistent" 9/8 mapping that is tuned to 230 cents - that would be an '''inadmissible''' tuning map, because we have added an extraneous extra 9/8 tuning that is worse than the original. In such situations we would throw away the extra inconsistent 9/8 entirely as it serves no purpose, and only use the consistent mapping. | As an example, if our tuning map has the "consistent" 9/8 tuned to 204, but where we have an extra "inconsistent" 9/8 mapping that is tuned to 230 cents - that would be an '''inadmissible''' tuning map, because we have added an extraneous extra 9/8 tuning that is worse than the original. In such situations we would throw away the extra inconsistent 9/8 entirely as it serves no purpose, and only use the consistent mapping. | ||