225/128

Interval information

Ratio	225/128
Factorization	2-7 × 32 × 52
Monzo	[-7 2 2⟩
Size in cents	976.5374¢
Names	diptolemaic augmented sixth, Neapolitan augmented sixth, marvel 5-limit harmonic seventh
Color name	Lyy6, layoyo 6th
FJS name	[math]\displaystyle{ \text{A6}^{5,5} }[/math]
Special properties	reduced, reduced harmonic
Tenney norm (log2 nd)	14.8138
Weil norm (log2 max(n, d))	15.6276
Wilson norm (sopfr(nd))	30
[sound info]
Open this interval in xen-calc

225/128, the diptolemaic augmented sixth or Neapolitan augmented sixth, is the interval between the 5-limit minor second, 16/15, and the major seventh, 15/8. It is flat of the Pythagorean augmented sixth by two syntonic commas, hence the first name, whereas the second name comes on account of this interval occurring in precisely this capacity in just Neapolitan scales.

It is a marvel comma, 225/224, sharp of the harmonic seventh, 7/4, and so tempering out 225/224, which is marvel temperament, equates the two. As such, it can also be called the marvel 5-limit harmonic seventh.

See also

• 256/225 – its octave complement
• Gallery of just intervals
• File:Ji-225-128-csound-foscil-220hz.mp3 – another sound example