27/22

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Interval information
Ratio 27/22
Factorization 2-1 × 33 × 11-1
Monzo [-1 3 0 0 -1
Size in cents 354.5471¢
Names rastmic neutral third,
Alpharabian tendoneutral third
Color name 1u3, lu 3rd
FJS name [math]\displaystyle{ \text{M3}_{11} }[/math]
Special properties reduced
Tenney norm (log2 nd) 9.21432
Weil norm (log2 max(n, d)) 9.50978
Wilson norm (sopfr(nd)) 22

[sound info]
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27/22, conventionally called the rastmic neutral third, is 243/242 (7.1 ¢) sharp of 11/9, and together with 11/9 makes 3/2, so that we obtain the two neutral triads, 1-11/9-3/2 and 1-27/22-3/2, with intervals of 11/9 and 27/22. It is the interval between 10/9 and 15/11, and 11/9 and 3/2 and their inversions. As this is the larger of two 11-limit neutral thirds obtained by modifying Pythagorean intervals by 33/32, it is dubbed the Alpharabian tendoneutral third in Alpharabian tuning.

Approximation

Edo approximations for 27/22 (354.55 ¢)
≤ 80edo, relative error ≤ 10%
Edo Step size Cents (¢) Absolute error (¢) Relative error (%)
7 2\7 342.86 -11.69 -6.82
10 3\10 360.00 +5.45 +4.54
17 5\17 352.94 -1.61 -2.28
20 6\20 360.00 +5.45 +9.09
24 7\24 350.00 -4.55 -9.09
27 8\27 355.56 +1.01 +2.27
34 10\34 352.94 -1.61 -4.55
37 11\37 356.76 +2.21 +6.81
44 13\44 354.55 -0.00 -0.01
51 15\51 352.94 -1.61 -6.83
54 16\54 355.56 +1.01 +4.54
61 18\61 354.10 -0.45 -2.28
64 19\64 356.25 +1.70 +9.08
68 20\68 352.94 -1.61 -9.10
71 21\71 354.93 +0.38 +2.26
78 23\78 353.85 -0.70 -4.56

See also