31edo: Difference between revisions

Xenwolf (talk | contribs)
m →Music: list formatting, a bit of space to make the wikitext readable as well
TallKite (talk | contribs)
added M2, m2 and A1 to the template, moved the primes-error table up to the top
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| Prime factorization = 31
| Prime factorization = 31
| Subgroup = 2.3.5.7.11
| Subgroup = 2.3.5.7.11
| Step size = 38.710
| Step size = 38.710¢
| Fifth type = meantone 13\31 696.77¢
| Fifth type = meantone 13\31 = 696.77¢
| Major 2nd = 5\31 = 194¢
| Minor 2nd = 3\31 = 116¢
| Augmented 1sn = 2\31 = 77¢
| Common uses = ~1/4-comma meantone<br/>general-purpose 11-limit system<br/>extended harmony utilizing dieses
| Common uses = ~1/4-comma meantone<br/>general-purpose 11-limit system<br/>extended harmony utilizing dieses
| Important MOS = diatonic (meantone) 5L2s 5553553 (18\31, 1\1)<br/>whole tone ([[hemithirds]]) 1L5s 555556 (5\31, 1\1)<br/>[[mohajira]] heptatonic 3L4s 5454544 (9\31, 1\1)<br/>[[mohajira]] decatonic 7L3s 4441441441 (9\31, 1\1)<br/>oneirotonic ([[A-Team]]) 5L3s 55255252 (12\31, 1\1)
| Important MOS = diatonic (meantone) 5L2s 5553553 (18\31, 1\1)<br/>whole tone ([[hemithirds]]) 1L5s 555556 (5\31, 1\1)<br/>[[mohajira]] heptatonic 3L4s 5454544 (9\31, 1\1)<br/>[[mohajira]] decatonic 7L3s 4441441441 (9\31, 1\1)<br/>oneirotonic ([[A-Team]]) 5L3s 55255252 (12\31, 1\1)
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== Theory ==
== Theory ==
Each step is equivalent to a frequency ratio of the 31st root of 2, or 38.71 [[cents]]. 31's perfect fifth is flat of the just interval 3:2 (over five cents), as befits a tuning supporting meantone, but the major third is less than a cent sharp (of just 5:4). 31's approximation of 7:4, a cent flat, is also very close to just. Because of these near-just values 31-et is relatively quite accurate and is in fact the sixth [[The Riemann Zeta Function and Tuning#Zeta EDO lists|zeta integral edo]]. Many [[7-limit]] JI scales are well-approximated in 31 (with tempering, of course). It also deals with the [[11-limit]] fairly well, and is consistent through it, but is the [[optimal patent val]] for the rank five temperament tempering out the 13-limit comma 66/65. It also provides the optimal patent val for mohajira, squares and casablanca in the 11-limit and huygens/meantone, squares, winston, lupercalia and nightengale in the 13-limit.
{| class="wikitable center-all"
! colspan="2" |
!prime 2
!prime 3
!prime 5
!prime 7
!prime 11
!prime 13
!prime 17
!prime 19
!prime 23
|-
! rowspan="2" |Error
!absolute (¢)
| 0
|  -5.18
|  +0.8
|  -1.1
|  -9.4
|  +11.1
|  +11.2
|  +12.2
|  -8.9
|-
![[Relative error|relative]] (%)
| 0
|  -13
|  +2
|  -3
|  -24
|  +29
|  +29
|  +31
|  -23
|-
! colspan="2" |[[nearest edomapping]]
|31
|18
|10
|25
|14
|22
|3
|8
|16
|-
! colspan="2" |[[fifthspan]]
| 0
|  +1
|  +4
|  +10
|  -13
|  +15
|  -5
|  -3
|  -6
|}Each step is equivalent to a frequency ratio of the 31st root of 2, or 38.71 [[cents]]. 31's perfect fifth is flat of the just interval 3:2 (over five cents), as befits a tuning supporting meantone, but the major third is less than a cent sharp (of just 5:4). 31's approximation of 7:4, a cent flat, is also very close to just. Because of these near-just values 31-et is relatively quite accurate and is in fact the sixth [[The Riemann Zeta Function and Tuning#Zeta EDO lists|zeta integral edo]]. Many [[7-limit]] JI scales are well-approximated in 31 (with tempering, of course). It also deals with the [[11-limit]] fairly well, and is consistent through it, but is the [[optimal patent val]] for the rank five temperament tempering out the 13-limit comma 66/65. It also provides the optimal patent val for mohajira, squares and casablanca in the 11-limit and huygens/meantone, squares, winston, lupercalia and nightengale in the 13-limit.


31edo's 12\31 generator (an approximate 21/16) supports [[A-Team]] and yields [[13edo#Modes_and_Harmony_in_the_Oneirotonic_Scale|8-note "oneirotonic" scales similar to those in 13edo]] but with the 9/8 and 5/4 better in tune; this temperament is also represented by [[13edo]], [[18edo]] and [[44edo]].
31edo's 12\31 generator (an approximate 21/16) supports [[A-Team]] and yields [[13edo#Modes_and_Harmony_in_the_Oneirotonic_Scale|8-note "oneirotonic" scales similar to those in 13edo]] but with the 9/8 and 5/4 better in tune; this temperament is also represented by [[13edo]], [[18edo]] and [[44edo]].
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=== Selected just intervals ===
=== Selected just intervals ===
{| class="wikitable center-all"
! colspan="2" |
!prime 2
!prime 3
!prime 5
!prime 7
!prime 11
!prime 13
!prime 17
!prime 19
!prime 23
|-
! rowspan="2" |Error
!absolute (¢)
| 0.0
| -5.18
| +0.8
| -1.1
| -9.4
| +11.1
| +11.2
| +12.2
| -8.9
|-
!relative (%)
| 0.0
| -13.4
| +2.0
| -2.8
| -24.2
| +28.6
| +28.9
| +31.4
| -23.0
|-
! colspan="2" |[[fifthspan]]
| 0
| +1
| +4
| +10
| -13
| +15
| -5
| -3
| -6
|}


==== 15-odd-limit interval mappings ====
==== 15-odd-limit interval mappings ====