32/31: Difference between revisions

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+ interval edo approximation table, not sure why this was missed
 
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{{Infobox Interval
{{Infobox Interval
| Name = 31st subharmonic, small tricesimoprimal quartertone
| Name = octave-reduced 31st subharmonic, small tricesimoprimal quartertone
| Color name = 31u2, thiwu 2nd
| Color name = 31u2, thiwu 2nd
| Sound = Ji-32-31-csound-foscil-220hz.mp3
| Sound = Ji-32-31-csound-foscil-220hz.mp3
}}
}}
'''32/31''' is the '''small tricesimoprimal quartertone''' measuring about 55{{cent}}. It differs from [[33/32]], the undecimal quartertone, by [[1024/1023]] (approx. 1.69{{cent}}). It differs from [[31/30]], another tricesimoprimal quartertone, by [[961/960]] (approx. 1.80{{cent}}); they together make [[16/15]].


'''32/31''' is the '''small tricesimoprimal quartertone''' measuring about 55{{cent}}. It differs from [[33/32]], the undecimal quartertone, by [[1024/1023]] (approx. 1.69{{cent}}). It differs from [[31/30]], another tricesimoprimal quartertone, by [[961/960]] (approx. 1.80{{cent}}); they together make [[16/15]].
== Approximation ==
This interval is approximated well (about 0.4{{c}} off) by [[22edo|1\22]] and extremely closely (about 0.0025{{c}} off) by [[131edo|6\131]].
{{Interval edo approximation}}
 
== Notation ==
This interval is significant in [[Helmholtz–Ellis notation]] as the formal comma to translate a Pythagorean interval to a nearby tricesimoprimal (31-limit) interval. The symbols are adapted from Persian quartertones accidentals invented by {{w|Ali-Naqi Vaziri}}.
 
== Temperaments ==
This interval can serve as a generator for the [[escapade]] temperament (which both 22 and 131edo, among others, [[support]]).


== See also ==
== See also ==
* [[31/16]] – its [[octave complement]]
* [[31/16]] – its [[octave complement]]
* [[31/24]] – its [[fifth complement]]
* [[31/24]] – its [[fourth complement]]
* [[Gallery of just intervals]]
* [[Gallery of just intervals]]


[[Category:Quartertone]]
[[Category:Quartertone]]

Latest revision as of 08:10, 6 October 2026

Interval information
Ratio 32/31
Subgroup monzo 2.31 [5 -1⟩
Size in cents 54.96443 ¢
Names octave-reduced 31st subharmonic,
small tricesimoprimal quartertone
Color name 31u2, thiwu 2nd
FJS name [math]\displaystyle{ \text{m2}_{31} }[/math]
Special properties superparticular,
reduced,
reduced subharmonic
Tenney norm (log2 nd) 9.9542
Weil norm (log2 max(n, d)) 10
Wilson norm (sopfr(nd)) 41

[sound info]
Open this interval in xen-calc

32/31 is the small tricesimoprimal quartertone measuring about 55 ¢. It differs from 33/32, the undecimal quartertone, by 1024/1023 (approx. 1.69 ¢). It differs from 31/30, another tricesimoprimal quartertone, by 961/960 (approx. 1.80 ¢); they together make 16/15.

Approximation

This interval is approximated well (about 0.4 ¢ off) by 1\22 and extremely closely (about 0.0025 ¢ off) by 6\131.

Edo approximations for 32/31 (54.96 ¢)
≤ 80edo, relative error ≤ 10%
Edo Step size Cents (¢) Absolute error (¢) Relative error (%)
2 0\2 0.00 -54.96 -9.16
20 1\20 60.00 +5.04 +8.39
21 1\21 57.14 +2.18 +3.81
22 1\22 54.55 -0.42 -0.77
23 1\23 52.17 -2.79 -5.35
24 1\24 50.00 -4.96 -9.93
42 2\42 57.14 +2.18 +7.62
43 2\43 55.81 +0.85 +3.04
44 2\44 54.55 -0.42 -1.54
45 2\45 53.33 -1.63 -6.12
64 3\64 56.25 +1.29 +6.86
65 3\65 55.38 +0.42 +2.28
66 3\66 54.55 -0.42 -2.30
67 3\67 53.73 -1.23 -6.88

Notation

This interval is significant in Helmholtz–Ellis notation as the formal comma to translate a Pythagorean interval to a nearby tricesimoprimal (31-limit) interval. The symbols are adapted from Persian quartertones accidentals invented by Ali-Naqi Vaziri.

Temperaments

This interval can serve as a generator for the escapade temperament (which both 22 and 131edo, among others, support).

See also