33/32: Difference between revisions
Reverted. That would make 11/8 an "undecimal subdiminished fifth" |
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== See also == | == See also == | ||
* [[64/33]] – its [[octave complement]] | |||
* [[Gallery of just intervals]] | * [[Gallery of just intervals]] | ||
* [[32/31]] | * [[32/31]] |
Revision as of 17:04, 18 September 2020
Interval information |
undecimal quarter tone,
undecimal comma
reduced,
reduced harmonic
[sound info]
33/32, the al-Farabi quarter tone[1], undecimal quarter tone, or undecimal comma, is a superparticular ratio which differs by a keenanisma (385/384), from the septimal quarter tone (36/35). Raising a just perfect fourth (4/3) by the al-Farabi quarter-tone leads to the undecimal super-fourth (11/8). Raising it instead by 36/35 leads to the septimal super-fourth (48/35) which approximates 11/8.
Arguably 33/32 could have been used as a melodic interval in the Greek Enharmonic Genus. The resulting tetrachord would include 32:33:34 within the interval of a perfect fourth. This ancient Greek scale can be approximated in 22edo and 24edo, if the comma 1089/1088 is tempered so that 33/32 and 34/33 are equated.
33/32 is significant in Functional Just System as the undecimal formal comma which translates a Pythagorean interval to a nearby undecimal interval. Apart from the aforementioned relationship between 4/3 and 11/8, it is also the interval between 32/27 and 11/9, and between 9/8 and 12/11.
See also
References
- ↑ The name goes back to Abu Nasr Al-Farabi (in Western reception also Alpharabius), see wikipedia:Al-Farabi