79/64
| Interval information |
septuacesimononal harmonic submajor third
reduced harmonic
(Shannon, [math]\displaystyle{ \sqrt{nd} }[/math])
79/64 is the octave-reduced 79th harmonic, which falls into the interval category of submajor thirds. It is lower than 5/4 by the interval of 80/79, very nearly the syntonic comma, 81/80.
Prime 79
Prime 79 is surprisingly versatile for its size, noting that its neighboring composites: 77, 78, 80, and 81, all belong to the 13-limit. As a result, some high-accuracy 13-limit structures have a natural route to incorporate prime 79: an example being phaotic ({256000/255879}), where (81/80)2 is equated to 40/39; naturally this results in 80/79 and 79/78 becoming additional interpretations of the syntonic comma, with equating it to 78/77 (the comma here being 2080/2079) being another step that can be taken to bridge it to primes 7 and 11.
A notable delta-rational chord involving prime 79 is 64:79:94, a compressed major triad, involving the subfifth 47/32, which is close to that of 9edo. A good approximation of this chord is hence found as [0 11 20]\36.