140/81
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| 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{nd}[/math]) |
~4.24167 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.
Approximation
It is perfectly approximated by 19edo (15\19), with an error of 0.05 cents, and hence equally well done by the enneadecal temperament.