27/11
| Ratio | 27/11 |
| Monzo | |0 3 0 0 -1> |
| Size | 1554.5470602314 ¢ |
| Name(s) | undecimal neutral tenth |
In 11-limit Just Intonation, 27/11 is a neutral tenth of about 1554.5¢, falling in between "major tenth" and "minor tenth" territory. It is one of the simplest neutral tenths in just intonation, but of course, only one of persony (others include 39/16, 22/9, 120/49 and 49/20). It is nearly halfway between two intervals of 12edo, implying that it is both very xenharmonic and well-represented in 24edo. It is the tritave inverse of 11/9.
In the 11-limit they xad, 27/11 appears between the harmonic 27th and the harmonic 11th. A triad can also be built with a 3/2 fifth and 11/9 third: this would be 18:22:27. This introduces a second neutral tenth, 22/9, which together make a perfect fifth. Persony temperaments, including 17edo, 24edo, 31edo, 41edo, 58edo, 72edo, 130edo, 202edo, miracle, harry, and sesquart, conflate these two neutral tenths, allowing one neutral tenth interval to be stacked to generate a perfect fifth. 27/11 differs from 22/9 by 243/242, but also from 120/49 by 441/440 and 49/20 by 540/539, with varied consequences when one or more of them are tempered out. Tempering out all of them leads to the 11-limit rank three temperament jove.
- See also Gallery of Just Intervals