121/81

Interval information

Ratio	121/81
Factorization	3-4 × 112
Monzo	[0 -4 0 0 2⟩
Size in cents	694.8159¢
Name	Alpharabian narrow fifth
Color name	1oo5, lolo 5th
FJS name	[math]\displaystyle{ \text{d5}^{11,11} }[/math]
Special properties	reduced
Tenney norm (log2 nd)	13.2587
Weil norm (log2 max(n, d))	13.8377
Wilson norm (sopfr(nd))	34
Open this interval in xen-calc

121/81, the Alpharabian narrow fifth (694.8¢), is a rastma 243/242 (7.1¢) below the just fifth 3/2. It is the interval created by stacking two 11/9 neutral thirds, and can be considered a meantone fifth. It differs from the marvellous fifth 112/75 by 3025/3024. Since 38edo represents 11/9 near perfectly, it also represents this near perfectly as well.

When treated as a meantone fifth, it is incredibly close to 1/3-comma meantone, three of these intervals differing from 5/3 by only the parimo.

See also

• 162/121 - its octave complement
• 729/484 - the Alpharabian wide fifth
• Gallery of just intervals