Alpharabian tuning: Difference between revisions
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Additional information about the basics of the tuning's interval naming scheme |
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The '''Alpharabian tuning''' is an [[11-limit]] version of [[just intonation]]- specifically the version that is limited to the 2.3.11 subgroup. | The '''Alpharabian tuning''' is an [[11-limit]] version of [[just intonation]]- specifically the version that is limited to the 2.3.11 subgroup. As a significant portion of this tuning system is currently being pioneered by [[User:Aura|Aura]], see [[User:Aura/Aura's Ideas on Tonality|Aura's Ideas on Tonality]] for more details. | ||
In terms of the interval naming scheme, there are several fundamental premises in Alpharabian tuning: | |||
* Intervals that are in the 2.11 subgroup are all considered Alpharabian intervals. | |||
* Intervals that result from the modification of a Pythagorean interval by [[1089/1024]] are labeled similarly to those modified in the equivalent fashion by [[2187/2048]], the only difference being that modification by 1089/1024 results in an Alpharabian interval rather than a Pythagorean interval. | |||
* Since 1089/1024 is (33/32)^2, modifying a Pythagorean interval by [[33/32]] always results in an interval that is considered "Alpharabian". | |||
In addition to that, there's also at least one known secondary premise at play: | |||
* As both the [[243/242|rastma]] and [[1331/1296]] are [[Diatonic, Chromatic, Enharmonic, Subchromatic|subchromas]] that form differences between members of the 2.11 subgroup and Pythagorean intervals, both of these subchromas belong to a set of intervals defining different interval sets within Alpharabian tuning, and subchromas within this particular interval set help define the differences between Pythagorean, Alpharabian and Betarabian intervals. | |||
The following rules are directly derived from the above premises: | |||
* Generally, intervals that result from the modification of a Pythagorean interval by 33/32 take either the 'parasuper' or 'parasub' prefixes, however, there are a number of special cases... | |||
:* Augmentation of a Perfect Fourth or Perfect Fifth by 33/32 results in a Paramajor interval | |||
:* Dimunition of a Perfect Fourth or Perfect Fifth by 33/32 results in a Paraminor interval | |||
:* Augmentation of a Pythagorean Minor interval by 33/32 results in a Lesser Neutral interval | |||
:* Dimunition of a Pythagorean Major interval by 33/32 results in a Greater Neutral interval | |||
* Generally, intervals that result that result from the modification of a Pythagorean interval by 1331/1296 take either the 'super' or 'sub' prefixes, with these prefixes generally being stacked where multiple such modifications occur, however, there are some significant caveats... | |||
:* Augmentation of a Pythagorean Minor interval by a single 1331/1296 results in a Supraminor interval, but a second such augmentation results in a Betarabian Major interval due to said interval differing from the nearby Alpharabian Major (covered under modifications by 1089/1024) by a rastma. | |||
:* Dimunition of a Pythagorean Major interval by a single 1331/1296 results in a Submajor interval, but a second such dimunition results in a Betarabian Minor interval due to said interval differing from the nearby Alpharabian Minor (covered under modifications by 1089/1024) by a rastma. | |||
[[Category:Tuning]] | [[Category:Tuning]] | ||
[[Category:Alpharabian| ]] <!-- main article --> | [[Category:Alpharabian| ]] <!-- main article --> | ||