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Interval information
Ratio 140/81
Factorization 22 × 3-4 × 5 × 7
Monzo [2 -4 1 1
Size in cents 947.31962¢
Name septimal inframinor seventh
Color name zy7, zoyo 7th
FJS name [math]\text{m7}^{5,7}[/math]
Special properties reduced
Tenney height (log2 nd) 13.4691
Weil height (log2 max(n, d)) 14.2586
Wilson height (sopfr (nd)) 28
Harmonic entropy
(Shannon, [math]\sqrt{n\cdot d}[/math])
~4.56095 bits

[sound info]
open this interval in xen-calc

140/81, the septimal inframinor seventh is a 7-limit interseptimal ratio of about 947 cents. It is flat of a minor seventh 16/9 by a septimal quartertone 36/35, flat of a subminor seventh 7/4 by a syntonic comma 81/80, and sharp of a supermajor sixth 12/7 by a sensamagic comma 245/243.

Notice it is also sharp of the just major sixth 5/3 by a subminor second 28/27. For this fact it is useful in the sensamagic dominant chord where it functions as a dissonance yet to be resolved down to the major sixth. The canou temperament targets this progression and uses it as one of the generators.


It is perfectly approximated by 19edo (15\19), with an error of 0.05 cents, and hence equally well done by the enneadecal temperament.

See also