16/11

In 11-limit just intonation, 16/11 is an undecimal subfifth measuring about 648.7¢. It is the inversion of 11/8, the undecimal superfourth. While the name "undecimal subfifth" suggests some variation of a perfect fifth, the subfifth is generally considered an interval in its own right being like neither a perfect fifth nor the tritone. Accordingly, this interval can also be called the undecimal minor fifth since the tempered version found in 24edo, was dubbed the "minor fifth" by Ivan Wyschnegradsky. Furthermore, given its connections to Alpharabian tuning, it can also be somewhat similarly dubbed the Axirabian paraminor fifth or even the just paraminor fifth- see the history of Aura's Ideas on Functional Harmony for explanation of the modified names.

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Major fourth and minor fifth

The character of this interval is something very unique in that it produces a sound of overtones that resembles that of a large bell. Furthermore, the hands of a good composer, 16/11 has decent potential as the interval between the root and fifth of a chord. That said, even the best triads that utilize it in this capacity- such as 44:55:64- must be handled with some measure of care as the rather dissonant nature of this interval provides a sense of tension, albeit less so than with diminished triads.

16/11

See also