21/20: Difference between revisions
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| Monzo = -2 1 -1 1 | | Monzo = -2 1 -1 1 | ||
| Cents = 84.4672 | | Cents = 84.4672 | ||
| Name = minor semitone, <br>large septimal chroma | | Name = septimal minor semitone, <br>large septimal chroma | ||
| Color name = zg2, zogu 2nd | | Color name = zg2, zogu 2nd | ||
| FJS name = m2<sup>7</sup><sub>5</sub> | | FJS name = m2<sup>7</sup><sub>5</sub> | ||
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'''21/20''' is a small semitone of about 85 cents. It may be found in [[7-limit]] [[just intonation]] as, for example, the difference between [[8/7]] and [[6/5]], or between [[5/3]] and [[7/4]]. | '''21/20''' is a small semitone of about 85 cents. It may be found in [[7-limit]] [[just intonation]] as, for example, the difference between [[8/7]] and [[6/5]], or between [[5/3]] and [[7/4]]. | ||
== Terminology == | |||
21/20 is traditionally called a ''chroma'', perhaps for its proximity (and conflation in systems like septimal [[meantone]]) with the major chroma [[135/128]]. However, it is a ''diatonic semitone'' in both [[Helmholtz-Ellis notation]] and [[Functional Just System]], viewed as the Pythagorean minor second [[256/243]] altered by [[5120/5103]]. [[Marc Sabat]] has taken to call it the ''minor diatonic semitone'' in the same material where [[15/14]] is also named as the major chromatic semitone<ref>[https://marsbat.space/pdfs/crystal-growth.pdf Marc Sabat (2008) Three Crystal Growth Algorithms in 23-limit constrained Harmonic Space]</ref>. | |||
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== See also == | == See also == | ||
Revision as of 14:25, 3 March 2021
| Interval information |
large septimal chroma
reduced
[sound info]
21/20 is a small semitone of about 85 cents. It may be found in 7-limit just intonation as, for example, the difference between 8/7 and 6/5, or between 5/3 and 7/4.
Terminology
21/20 is traditionally called a chroma, perhaps for its proximity (and conflation in systems like septimal meantone) with the major chroma 135/128. However, it is a diatonic semitone in both Helmholtz-Ellis notation and Functional Just System, viewed as the Pythagorean minor second 256/243 altered by 5120/5103. Marc Sabat has taken to call it the minor diatonic semitone in the same material where 15/14 is also named as the major chromatic semitone[1].
See also
- 40/21 – its octave complement
- 10/7 – its fifth complement
- List of superparticular intervals
- Gallery of just intervals
- Septisemi temperaments, where it is tempered out
- Wikipedia: Septimal chromatic semitone