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Interval information
Ratio 980/729
Factorization 22 × 3-6 × 5 × 72
Monzo [2 -6 1 2
Size in cents 512.23552¢
Name complex sensamagic fourth
Color name zzy5, zozoyo 5th
FJS name [math]\text{d5}^{5,7,7}[/math]
Special properties reduced
Tenney height (log2 nd) 19.4464
Weil height (log2 max(n, d)) 19.8733
Wilson height (sopfr (nd)) 41
Harmonic entropy
(Shannon, [math]\sqrt{n\cdot d}[/math])
~4.43321 bits
open this interval in xen-calc

980/729, the complex sensamagic fourth is a 7-limit interval of about 512 cents, sharp of a perfect fourth (4/3) by a sensamagic comma (245/243).

It arises in just intonation as the difference between the supermajor third 9/7 and the semidiminished seventh 140/81, making it a critical tempering target in the Sensamagic dominant chord. However, its distinction from 4/3 is emphasised in the canou family of temperaments, through its accessibility by two steps of the 81/70-generator.

See also