31edo: Difference between revisions
Tristanbay (talk | contribs) →Ups and downs notation: Changed to new template |
→Theory: I don't think that part's needed, actually |
||
| (25 intermediate revisions by 8 users not shown) | |||
| Line 1: | Line 1: | ||
{{ | {{Interwiki | ||
| en = 31edo | |||
| de = 31-EDO | | de = 31-EDO | ||
| es = 31 EDO | | es = 31 EDO | ||
| ja = 31平均律 | | ja = 31平均律 | ||
| zh = 31平均律 | |||
}} | }} | ||
{{Infobox ET}} | {{Infobox ET}} | ||
| Line 18: | Line 19: | ||
Other ways in which 31edo is especially accurate is that it represents a record in [[Pepper ambiguity]] in the [[7-odd-limit|7-]], [[9-odd-limit|9-]], and [[11-odd-limit]], which it is consistent through. It is also a [[the Riemann zeta function and tuning #Zeta EDO lists|strict zeta edo]], meaning that it is a zeta peak, zeta peak integer, zeta integral, and zeta gap edo all at once. | Other ways in which 31edo is especially accurate is that it represents a record in [[Pepper ambiguity]] in the [[7-odd-limit|7-]], [[9-odd-limit|9-]], and [[11-odd-limit]], which it is consistent through. It is also a [[the Riemann zeta function and tuning #Zeta EDO lists|strict zeta edo]], meaning that it is a zeta peak, zeta peak integer, zeta integral, and zeta gap edo all at once. | ||
One step of 31edo, measuring about 38.7{{c}}, is called a [[diesis]] because it stands in for several intervals called ''dieses'' (most notably, [[128/125]] and [[648/625]]) which are tempered out in [[12edo]]. The diesis is a defining sound of 31edo; when it does not appear directly in a scale, it often shows up as the difference between two or more intervals of a similar size. The diesis is demonstrated in [[SpiralProgressions]]. [[Zhea Erose]]'s 31edo music uses the interval frequently. | One step of 31edo, measuring about 38.7{{c}}, is called a [[diesis]] because it stands in for several intervals called ''dieses'' (most notably, [[128/125]] and [[648/625]]) which are tempered out in [[12edo]]. The diesis is a defining sound of 31edo; when it does not appear directly in a scale, it often shows up as the difference between two or more intervals of a similar size. The diesis is demonstrated in [[SpiralProgressions]]. [[Zhea Erose]]'s 31edo music uses the interval frequently. | ||
In terms of interval categories, because 31edo is a meantone system, the major and minor seconds, thirds, sixth, and sevenths on the chain of fifths are equated to [[5-limit]] intervals, those being [[16/15]], [[10/9]], [[6/5]], [[5/4]], and their [[octave complement]]s. 31edo maps the chromatic semitone to two steps, meaning there are "[[neutral (interval quality)|neutral]]" intervals between minor and major ones, which are not found in [[12edo]]. They can be represented by [[11-limit]] intervals, with [[11/10]]~[[12/11]] being a neutral second, and [[11/9]]~[[27/22]] a neutral third. One step in the other direction from the classical intervals are the subminor and supermajor intervals, which can be seen as intervals of prime [[7/1|7]]. The subminor second is [[21/20]]~[[28/27]], the supermajor second [[8/7]], the subminor third [[7/6]], and the supermajor third [[9/7]]~[[14/11]]. 31edo thus has five varieties of seconds and thirds each, which is much more than the two varieties available in 12edo. | |||
=== Prime harmonics === | === Prime harmonics === | ||
| Line 25: | Line 28: | ||
=== As a tuning of other temperaments === | === As a tuning of other temperaments === | ||
Besides meantone, 31edo can be used as a tuning for [[mohajira]], [[mothra]] | Besides meantone, 31edo can be used as a tuning for [[mohajira]], [[mothra]] or less optimally [[miracle]] and [[valentine]]. These temperaments split 31edo's fifth, at 18 steps, into two, three, six, and nine equal parts. In fact, 31edo can be defined as the unique temperament that [[tempering out|tempers out]] [[81/80]], [[99/98]], [[121/120]], and [[126/125]]. | ||
31edo also [[support]]s [[orwell]], which splits the [[3/1|perfect twelfth]] into seven equal parts of ~7/6. Another notable temperament it supports is [[myna]], which | If we split the meantone [[generator]] of ~3/2 into two neutral thirds, each representing [[11/9]]~[[27/22]], then we get the [[2.3.5.11 subgroup|2.3.5.11-subgroup]] temperament [[mohaha]], tempering out [[121/120]] and [[243/242]]. We can then map [[7/4]] to the semi-diminished seventh (-13 generators), tempering out [[385/384]], to get the full 11-limit mohajira temperament, which maps 7/6, 6/5, 11/9, 5/4, and 9/7 equidistant from each other. Alternatively, we can use the septimal meantone mapping of 7/4 (+20 generators) to get [[migration]]. Mohajira and [[migration]] merge in 31edo, and create a near-optimal 11-limit meantone structure in one unified system. | ||
The supermajor second [[8/7]] is mapped to a third of the perfect fifth in 31edo, thus tempering out [[1029/1024]], supporting [[slendric]] in the [[2.3.7 subgroup|2.3.7-subgroup]]. Slendric is a [[cluster temperament]] with 5 clusters of notes in an octave, each with nearby intervals separated by the interval found at -5 generators, or 1 step of 31edo, representing [[49/48]]~[[64/63]]. For example, 9/8, 8/7, and 7/6 are one step apart from each other, as well as 9/7, 21/16, and 4/3. 31edo supports the full 7-limit extension mothra, which tempers out 81/80, thus equating the 49/48~64/63 spacer with [[36/35]], so that 9/8~10/9, 8/7, 7/6, and 6/5 are all mapped equidistantly, as well as 5/4, 9/7, 21/16, and 4/3. Mothra splits into two 11-limit extensions: [[Gamelismic clan#Undecimal mothra|undecimal mothra]] (26 & 31) tempering out [[99/98]], and [[mosura]] (31 & 36) tempering out [[176/175]]. | |||
[[Miracle]] temperament splits the slendric generator in two parts and the perfect fifth in six, each representing [[15/14]]~[[16/15]], thus tempering out [[225/224]], so that 5/4 is found at -7 generators. The 11-limit version of miracle sets 11/9 to the neutral third, with prime 11 mapped at +15 generators. While 31edo supports miracle, a more accurate tuning is [[72edo]]. [[Valentine]] temperament splits the slendric generator in three parts and the perfect fifth in nine, each representing [[21/20]], tempering out [[126/125]]. Valentine can also be seen as [[Carlos Alpha]] but with octaves added. The canonical 11-limit extension equates the step with [[22/21]], thus tempering out [[121/120]], [[176/175]], and [[441/440]]. | |||
31edo also [[support]]s [[orwell]], which splits the [[3/1|perfect twelfth]] into seven equal parts of ~7/6. Three of these reach [[8/5]], and two reach [[11/8]], with 1–7/6–11/8–8/5 being the [[orwell tetrad]]. Commas tempered out by orwell include [[99/98]], [[121/120]], [[176/175]], and [[385/384]], among others. | |||
Another notable temperament it supports is [[myna]], which is generated by the minor third, and sets the intervals [[7/6]], [[6/5]], 11/9~[[16/13]], 5/4, and 9/7 being equidistant. Like mohajira, it creates five interval categories, but with 126/125 tempered out instead of 81/80. | |||
31edo also supports [[squares]], which splits the [[8/3|perfect eleventh]] into four equal parts, each representing [[14/11]]~9/7, two of which make [[18/11]], and four of which make [[8/3]]. The [[2.3.7.11-subgroup|2.3.7.11 subgroup]] version of this temperament is sometimes known as ''skwares'', tempering out 99/98 and 243/242. Then, prime [[5/1|5]] is found by tempering out [[81/80]], completing the 11-limit. | |||
Another temperament supported by 31edo is [[würschmidt]], which is generated by 5/4, such that 8 intervals of 5/4 reach [[6/1]]. Würschmidt extends to the 7- and 11-limit through the skwares mapping, also creating 5 interval categories, with the thirds being 7/6, 6/5, 11/9, 5/4, and 14/11~9/7, each equidistant from each other. | |||
=== Subsets and supersets === | === Subsets and supersets === | ||
31edo is the 11th [[prime edo]], following [[29edo]] and coming before [[37edo]]. It does not contain any nontrivial subset edos, though it contains [[31ed4]]. [[62edo]], which | 31edo is the 11th [[prime edo]], following [[29edo]] and coming before [[37edo]]. It does not contain any nontrivial subset edos, though it contains [[31ed4]]. [[62edo]] and [[93edo]], which double and triple it, respectively, provide alternative ways to extend the temperament to the 13-, 17-, and 19-limits, and in the case of 93edo, even to the 23-limit. | ||
[[217edo]], which slices the edostep in seven, provides a very good correction of primes 3, 13, 17 and 31, and is consistent in the 21-odd-limit. | |||
== Intervals == | == Intervals == | ||
{{See also|Table of 31edo intervals|31edo/Individual degrees | {{See also|Table of 31edo intervals|31edo/Individual degrees}} | ||
{| class="wikitable center- | {| class="wikitable center-1 right-2" | ||
|- | |||
! # | |||
! Cents | |||
! Interval categories | |||
! Approximate ratios<ref group="note">As a 13-limit temperament, with additional ratios of 17, 19, and 23. Inconsistent intervals are in ''italics''.</ref> | |||
! [[Kite's ups and downs notation|Ups and downs notation]] | |||
|- | |||
| 0 | |||
| 0.0 | |||
| Unison | |||
| [[1/1]] | |||
| {{UDnote|step=0}} | |||
|- | |||
| 1 | |||
| 38.7 | |||
| Super-unison | |||
| [[36/35]], [[45/44]], [[49/48]], [[50/49]], [[64/63]], [[128/125]] | |||
| {{UDnote|step=1}} | |||
|- | |||
| 2 | |||
| 77.4 | |||
| Subminor second | |||
| [[21/20]], [[22/21]], [[23/22]], [[25/24]], [[28/27]] | |||
| {{UDnote|step=2}} | |||
|- | |||
| 3 | |||
| 116.1 | |||
| Minor second | |||
| [[14/13]], [[15/14]], [[16/15]] | |||
| {{UDnote|step=3}} | |||
|- | |||
| 4 | |||
| 154.8 | |||
| Neutral second | |||
| [[11/10]], [[12/11]], [[13/12]], [[35/32]] | |||
| {{UDnote|step=4}} | |||
|- | |||
| 5 | |||
| 193.5 | |||
| Major second | |||
| [[9/8]], [[10/9]], [[19/17]], [[28/25]] | |||
| {{UDnote|step=5}} | |||
|- | |||
| 6 | |||
| 232.3 | |||
| Supermajor second | |||
| [[8/7]] | |||
| {{UDnote|step=6}} | |||
|- | |- | ||
! | | 7 | ||
| 271.0 | |||
| Subminor third | |||
| [[7/6]] | |||
| {{UDnote|step=7}} | |||
|- | |||
| 8 | |||
| 309.7 | |||
| Minor third | |||
| [[6/5]], [[25/21]], ''[[13/11]]'' | |||
| {{UDnote|step=8}} | |||
|- | |||
| 9 | |||
| 348.4 | |||
| Neutral third | |||
| [[11/9]], [[16/13]] | |||
| {{UDnote|step=9}} | |||
|- | |||
| 10 | |||
| 387.1 | |||
| Major third | |||
| [[5/4]] | |||
| {{UDnote|step=10}} | |||
|- | |||
| 11 | |||
| 425.8 | |||
| Supermajor third | |||
| [[9/7]], [[14/11]], [[23/18]], [[32/25]] | |||
| {{UDnote|step=11}} | |||
|- | |||
| 12 | |||
| 464.5 | |||
| Subfourth | |||
| [[13/10]], [[17/13]], [[21/16]] | |||
| {{UDnote|step=12}} | |||
|- | |||
| 13 | |||
| 503.2 | |||
| Perfect fourth | |||
| [[4/3]] | |||
| {{UDnote|step=13}} | |||
|- | |||
| 14 | |||
| 541.9 | |||
| Superfourth | |||
| [[11/8]], [[15/11]], [[26/19]], ''[[18/13]]'', [[48/35]] | |||
| {{UDnote|step=14}} | |||
|- | |||
| 15 | |||
| 580.6 | |||
| Augmented fourth | |||
| [[7/5]], [[25/18]], [[45/32]] | |||
| {{UDnote|step=15}} | |||
|- | |||
| 16 | |||
| 619.4 | |||
| Diminished fifth | |||
| [[10/7]], [[36/25]], [[64/45]] | |||
| {{UDnote|step=16}} | |||
|- | |||
| 17 | |||
| 658.1 | |||
| Subfifth | |||
| [[16/11]], [[19/13]], [[22/15]], ''[[13/9]]'', [[35/24]] | |||
| {{UDnote|step=17}} | |||
|- | |||
| 18 | |||
| 696.8 | |||
| Perfect fifth | |||
| [[3/2]] | |||
| {{UDnote|step=18}} | |||
|- | |||
| 19 | |||
| 735.5 | |||
| Superfifth | |||
| [[20/13]], [[26/17]], [[32/21]] | |||
| {{UDnote|step=19}} | |||
|- | |||
| 20 | |||
| 774.2 | |||
| Subminor sixth | |||
| [[11/7]], [[14/9]], [[25/16]] | |||
| {{UDnote|step=20}} | |||
|- | |||
| 21 | |||
| 812.9 | |||
| Minor sixth | |||
| [[8/5]] | |||
| {{UDnote|step=21}} | |||
|- | |||
| 22 | |||
| 851.6 | |||
| Neutral sixth | |||
| [[13/8]], [[18/11]] | |||
| {{UDnote|step=22}} | |||
|- | |||
| 23 | |||
| 890.3 | |||
| Major sixth | |||
| [[5/3]], [[42/25]], ''[[22/13]]'' | |||
| {{UDnote|step=23}} | |||
|- | |||
| 24 | |||
| 929.0 | |||
| Supermajor sixth | |||
| [[12/7]] | |||
| {{UDnote|step=24}} | |||
|- | |||
| 25 | |||
| 967.7 | |||
| Subminor seventh | |||
| [[7/4]] | |||
| {{UDnote|step=25}} | |||
|- | |||
| 26 | |||
| 1006.5 | |||
| Minor seventh | |||
| [[9/5]], [[16/9]], [[25/14]], [[34/19]] | |||
| {{UDnote|step=26}} | |||
|- | |||
| 27 | |||
| 1045.2 | |||
| Neutral seventh | |||
| [[11/6]], [[20/11]], [[24/13]], [[64/35]] | |||
| {{UDnote|step=27}} | |||
|- | |||
| 28 | |||
| 1083.9 | |||
| Major seventh | |||
| [[13/7]], [[15/8]], [[28/15]] | |||
| {{UDnote|step=28}} | |||
|- | |||
| 29 | |||
| 1122.6 | |||
| Supermajor seventh | |||
| [[21/11]], [[27/14]], [[40/21]], [[44/23]], [[48/25]] | |||
| {{UDnote|step=29}} | |||
|- | |||
| 30 | |||
| 1161.3 | |||
| Sub-octave | |||
| [[35/18]], [[49/25]], [[63/32]], [[88/45]], [[96/49]], [[125/64]] | |||
| {{UDnote|step=30}} | |||
|- | |||
| 31 | |||
| 1200.0 | |||
| Octave | |||
| [[2/1]] | |||
| {{UDnote|step=31}} | |||
|} | |||
<references group="note" /> | |||
=== Proposed interval names and solfeges === | |||
{{See also|31edo solfege}} | |||
{| class="wikitable center-all right-2 left-4 left-7 left-10 mw-collapsible mw-collapsed" | |||
|+ style="white-space: nowrap;" | Table of proposed interval names and solfèges | |||
|- | |||
! # | |||
! Cents | ! Cents | ||
! colspan="3" | [[Kite's ups and downs notation|Ups and downs notation]]<br>([[Enharmonic unisons in ups and downs notation|EUs]]: vvA1 and vd2) | |||
! colspan="3" | [[Ups and downs notation]]<br>([[Enharmonic unisons in ups and downs notation|EUs]]: vvA1 and vd2) | |||
! colspan="3" | Extended pythagorean notation | ! colspan="3" | Extended pythagorean notation | ||
! colspan="3" | [[SKULO interval names|SKULO notation]] (S or {{nowrap|U {{=}} 1}}) | ! colspan="3" | [[SKULO interval names|SKULO notation]]<br>(S or {{nowrap|U {{=}} 1}}) | ||
|- | |- | ||
| 0 | | 0 | ||
| 0.0 | | 0.0 | ||
| P1 | | P1 | ||
| perfect unison | | perfect unison | ||
| Line 59: | Line 280: | ||
| 1 | | 1 | ||
| 38.7 | | 38.7 | ||
| ^1, d2 | | ^1, d2 | ||
| up-unison, dim 2nd | | up-unison, dim 2nd | ||
| Line 72: | Line 292: | ||
| 2 | | 2 | ||
| 77.4 | | 77.4 | ||
| A1, vm2 | | A1, vm2 | ||
| aug 1sn, downminor 2nd | | aug 1sn, downminor 2nd | ||
| Line 85: | Line 304: | ||
| 3 | | 3 | ||
| 116.1 | | 116.1 | ||
| m2 | | m2 | ||
| minor 2nd | | minor 2nd | ||
| Line 98: | Line 316: | ||
| 4 | | 4 | ||
| 154.8 | | 154.8 | ||
| ~2 | | ~2 | ||
| mid 2nd | | mid 2nd | ||
| Line 111: | Line 328: | ||
| 5 | | 5 | ||
| 193.5 | | 193.5 | ||
| M2 | | M2 | ||
| major 2nd | | major 2nd | ||
| Line 124: | Line 340: | ||
| 6 | | 6 | ||
| 232.3 | | 232.3 | ||
| ^M2 | | ^M2 | ||
| upmajor 2nd | | upmajor 2nd | ||
| Line 137: | Line 352: | ||
| 7 | | 7 | ||
| 271.0 | | 271.0 | ||
| vm3 | | vm3 | ||
| downminor 3rd | | downminor 3rd | ||
| Line 150: | Line 364: | ||
| 8 | | 8 | ||
| 309.7 | | 309.7 | ||
| m3 | | m3 | ||
| minor 3rd | | minor 3rd | ||
| Line 163: | Line 376: | ||
| 9 | | 9 | ||
| 348.4 | | 348.4 | ||
| ~3 | | ~3 | ||
| mid 3rd | | mid 3rd | ||
| Line 176: | Line 388: | ||
| 10 | | 10 | ||
| 387.1 | | 387.1 | ||
| M3 | | M3 | ||
| major 3rd | | major 3rd | ||
| Line 189: | Line 400: | ||
| 11 | | 11 | ||
| 425.8 | | 425.8 | ||
| ^M3 | | ^M3 | ||
| upmajor 3rd | | upmajor 3rd | ||
| Line 202: | Line 412: | ||
| 12 | | 12 | ||
| 464.5 | | 464.5 | ||
| v4 | | v4 | ||
| down-4th | | down-4th | ||
| Line 215: | Line 424: | ||
| 13 | | 13 | ||
| 503.2 | | 503.2 | ||
| P4 | | P4 | ||
| perfect 4th | | perfect 4th | ||
| Line 228: | Line 436: | ||
| 14 | | 14 | ||
| 541.9 | | 541.9 | ||
| ^4, ~4 | | ^4, ~4 | ||
| up-4th, mid 4th | | up-4th, mid 4th | ||
| Line 241: | Line 448: | ||
| 15 | | 15 | ||
| 580.6 | | 580.6 | ||
| A4, vd5 | | A4, vd5 | ||
| aug 4th, downdim 5th | | aug 4th, downdim 5th | ||
| Line 254: | Line 460: | ||
| 16 | | 16 | ||
| 619.4 | | 619.4 | ||
| ^A4, d5 | | ^A4, d5 | ||
| upaug 4th, dim 5th | | upaug 4th, dim 5th | ||
| Line 267: | Line 472: | ||
| 17 | | 17 | ||
| 658.1 | | 658.1 | ||
| v5, ~5 | | v5, ~5 | ||
| down-5th, mid 5th | | down-5th, mid 5th | ||
| Line 280: | Line 484: | ||
| 18 | | 18 | ||
| 696.8 | | 696.8 | ||
| P5 | | P5 | ||
| perfect 5th | | perfect 5th | ||
| Line 293: | Line 496: | ||
| 19 | | 19 | ||
| 735.5 | | 735.5 | ||
| ^5 | | ^5 | ||
| up-5th | | up-5th | ||
| Line 306: | Line 508: | ||
| 20 | | 20 | ||
| 774.2 | | 774.2 | ||
| vm6 | | vm6 | ||
| downminor 6th | | downminor 6th | ||
| Line 319: | Line 520: | ||
| 21 | | 21 | ||
| 812.9 | | 812.9 | ||
| m6 | | m6 | ||
| minor 6th | | minor 6th | ||
| Line 332: | Line 532: | ||
| 22 | | 22 | ||
| 851.6 | | 851.6 | ||
| ~6 | | ~6 | ||
| mid 6th | | mid 6th | ||
| Line 345: | Line 544: | ||
| 23 | | 23 | ||
| 890.3 | | 890.3 | ||
| M6 | | M6 | ||
| major 6th | | major 6th | ||
| Line 358: | Line 556: | ||
| 24 | | 24 | ||
| 929.0 | | 929.0 | ||
| ^M6 | | ^M6 | ||
| upmajor 6th | | upmajor 6th | ||
| Line 371: | Line 568: | ||
| 25 | | 25 | ||
| 967.7 | | 967.7 | ||
| vm7 | | vm7 | ||
| downminor 7th | | downminor 7th | ||
| Line 384: | Line 580: | ||
| 26 | | 26 | ||
| 1006.5 | | 1006.5 | ||
| m7 | | m7 | ||
| minor 7th | | minor 7th | ||
| Line 397: | Line 592: | ||
| 27 | | 27 | ||
| 1045.2 | | 1045.2 | ||
| ~7 | | ~7 | ||
| mid 7th | | mid 7th | ||
| Line 410: | Line 604: | ||
| 28 | | 28 | ||
| 1083.9 | | 1083.9 | ||
| M7 | | M7 | ||
| major 7th | | major 7th | ||
| Line 423: | Line 616: | ||
| 29 | | 29 | ||
| 1122.6 | | 1122.6 | ||
| ^M7 | | ^M7 | ||
| upmajor 7th | | upmajor 7th | ||
| Line 436: | Line 628: | ||
| 30 | | 30 | ||
| 1161.3 | | 1161.3 | ||
| v8 | | v8 | ||
| down-8ve | | down-8ve | ||
| Line 449: | Line 640: | ||
| 31 | | 31 | ||
| 1200.0 | | 1200.0 | ||
| P8 | | P8 | ||
| perfect 8ve | | perfect 8ve | ||
| Line 561: | Line 751: | ||
=== Ups and downs notation === | === Ups and downs notation === | ||
Spoken as up, sharp, upsharp, etc. Note that up can be respelled as downsharp. The gamut runs D, ^D/vD#, D#, Eb, ^Eb/vE, E, ^E, vF, F etc. | Spoken as up, sharp, upsharp, etc. Note that up can be respelled as downsharp. The gamut runs D, ^D/vD#, D#, Eb, ^Eb/vE, E, ^E, vF, F etc. | ||
{{Ups and downs sharpness | {{Ups and downs sharpness}} | ||
=== Neutral chain-of-fifths notation === | === Neutral chain-of-fifths notation === | ||
| Line 667: | Line 857: | ||
==== Evo flavor ==== | ==== Evo flavor ==== | ||
{{Sagittal chart|Evo}} | |||
==== Evo-SZ flavor ==== | |||
{{Sagittal chart|Evo-SZ}} | |||
Because it contains no Sagittal symbols, this Evo-SZ Sagittal notation is identical to Stein–Zimmerman notation. | |||
==== Revo flavor ==== | ==== Revo flavor ==== | ||
{{Sagittal chart}} | |||
We also have a diagram from the appendix to [[The Sagittal Songbook]] by [[Jacob Barton|Jacob A. Barton]], which gives multiple spellings for each pitch, and up to the double-apotome: | We also have a diagram from the appendix to [[The Sagittal Songbook]] by [[Jacob Barton|Jacob A. Barton]], which gives multiple spellings for each pitch, and up to the double-apotome: | ||
[[File:31edo Sagittal.png|800px]] | [[File:31edo Sagittal.png|800px]] | ||
== Relationship to 12edo == | == Relationship to 12edo == | ||
| Line 774: | Line 943: | ||
| 3.584 | | 3.584 | ||
|} | |} | ||
* 31et is lower in relative error than any previous equal temperaments in the 7-, 11-, 13-, and 17-limit. The next equal temperaments doing better in those subgroups are 72, 72, 41, and 46, respectively. | * 31et is lower in relative error than any previous equal temperaments in the 7-, 11-, 13-, and 17-limit. The next equal temperaments doing better in those subgroups are [[72edo|72]], 72, [[41edo|41]], and [[46edo|46]], respectively. | ||
* 31et excels in the 2.5.7 subgroup (the JI chord 4:5:7 is represented highly [[consistent]]ly: to [[consistency #Consistency to distance d|distance]] 10.36). In 2.5.7 it tempers out the didacus comma [[3136/3125]] and the quince comma [[823543/819200]], thus also tempering out the very small [[rainy comma]], the simplest 2.5.7 comma tempered out by the 7-limit microtemperament [[171edo]]. | * 31et excels in the [[2.5.7 subgroup]] (the JI chord [[4:5:7]] is represented highly [[consistent]]ly: to [[consistency #Consistency to distance d|distance]] 10.36). In 2.5.7 it tempers out the didacus comma [[3136/3125]] and the quince comma [[823543/819200]], thus also tempering out the very small [[rainy comma]], the simplest 2.5.7 comma tempered out by the 7-limit microtemperament [[171edo]]. | ||
* In the 17-limit it tempers out [[120/119]], equating the otonal tetrad of [[4:5:6:7]] and the inversion of the [[10:12:15:17]] minor tetrad. | * In the [[17-limit]] it tempers out [[120/119]], equating the otonal tetrad of [[4:5:6:7]] and the inversion of the [[10:12:15:17]] minor tetrad. | ||
=== Uniform maps === | === Uniform maps === | ||
| Line 1,064: | Line 1,233: | ||
| 0.42 | | 0.42 | ||
| Sathurugu | | Sathurugu | ||
| | | Minisma | ||
|} | |} | ||
<references group="note" /> | |||
=== Rank-2 temperaments === | === Rank-2 temperaments === | ||
| Line 1,173: | Line 1,343: | ||
| (P8, ccP4/5) | | (P8, ccP4/5) | ||
|} | |} | ||
<nowiki/>* [[Normal | <nowiki/>* [[Normal forms #Equave-reduced-generator form|Octave-reduced form]], reduced to the first half-octave, and [[normal forms #Minimal-generator form|minimal form]] in parentheses if distinct | ||
== Octave stretch or compression == | == Octave stretch or compression == | ||
| Line 1,267: | Line 1,437: | ||
* 17 is sharp, like 13. In fact, the 17:13 ratio is matched within a tenth of a cent. | * 17 is sharp, like 13. In fact, the 17:13 ratio is matched within a tenth of a cent. | ||
* 19 is also sharp, like 13 and 17. The 19:17 ratio is about one cent sharp. 31edo could be considered a tuning of the 2.5.7.13.17.19 subgroup, on which it is consistent (see [[ | * 19 is also sharp, like 13 and 17. The 19:17 ratio is about one cent sharp. 31edo could be considered a tuning of the 2.5.7.13.17.19 subgroup, on which it is consistent (see [[Quince clan#Mercy|mercy temperament]]). | ||
* 23 is about as flat as 11. The chromatic semitone is about half a cent off from 23:22. 31edo could be considered a tuning of the 2.3.5.7.11.23 subgroup, on which it is consistent. | * 23 is about as flat as 11. The chromatic semitone is about half a cent off from 23:22. 31edo could be considered a tuning of the 2.3.5.7.11.23 subgroup, on which it is consistent. | ||
* 27 is quite flat, as it's 3<sup>3</sup> and the error from the meantone fifths accumulates. | * 27 is quite flat, as it's 3<sup>3</sup> and the error from the meantone fifths accumulates. | ||
| Line 1,326: | Line 1,496: | ||
=== Various subsets === | === Various subsets === | ||
; Lists of scales | |||
* [[31edo modes]] | * [[31edo modes]] | ||
* [[Strictly proper]] [[Strictly proper 7-tone 31edo scales|7-tone 31edo scales]] | * [[Strictly proper]] [[Strictly proper 7-tone 31edo scales|7-tone 31edo scales]] | ||
* Interesting (to somebody) [[9-tone 31edo scales]] | * Interesting (to somebody) [[9-tone 31edo scales]] | ||
* the [[Erose–McClain double mode]]s, which are [[nonoctave]] | * the [[Erose–McClain double mode]]s, which are [[nonoctave]] | ||
; Individual scales | |||
* the [[Euler–Fokker genus]] (technically [[JI]] but representable in 31) | * the [[Euler–Fokker genus]] (technically [[JI]] but representable in 31) | ||
* the [[altered pentad]] | * the [[altered pentad]] | ||
* [[diasem]] (2.3.7 subgroup scale; 5 2 5 1 5 2 5 1 5 or 5 1 5 2 5 1 5 2 5 in 31edo) | * [[diasem]] (2.3.7 subgroup scale; 5 2 5 1 5 2 5 1 5 or 5 1 5 2 5 1 5 2 5 in 31edo) | ||
* the [[moon dust]] scale{{idio}} (technically [[JI]] but representable in 31) | |||
== Instruments == | == Instruments == | ||
| Line 1,345: | Line 1,518: | ||
=== Other Instruments === | === Other Instruments === | ||
[[File:31edo array kalimba.jpg|none|thumb|640x640px|31edo array kalimba built by Tristan Bay; 3 octaves, 94 keys, and laid out in circle-of-fourths meantone tuning]] | [[File:31edo array kalimba.jpg|none|thumb|640x640px|31edo array kalimba built by [[Tristan Bay]]; 3 octaves, 94 keys, and laid out in circle-of-fourths meantone tuning]] | ||
=== Lumatone === | === Lumatone === | ||
| Line 1,352: | Line 1,525: | ||
=== Skip fretting === | === Skip fretting === | ||
'''[[Skip fretting system 31 2 9]]''' is a [[skip fretting]] system for 31edo. | '''[[Skip fretting system 31 2 9]]''' is a [[skip fretting]] system for 31edo. | ||
'''[[Skip fretting system 31 3 7]]''' is another skip fretting system for 31edo. | '''[[Skip fretting system 31 3 7]]''' is another skip fretting system for 31edo. | ||
'''Skip fretting system 31 2 5''' is another skip fretting system for 31edo. All examples on this page are for 7-string [[guitar]]. | '''Skip fretting system 31 2 5''' is another skip fretting system for 31edo. All examples on this page are for 7-string [[guitar]]. | ||
| Line 1,394: | Line 1,565: | ||
* [[MicroPedagogyCollective]] – is at work (as of 2012) producing demonstrative material which will encourage and enable more people to learn this system. There have been two [[ThirtyOneToneSinginCamp]]s as well. | * [[MicroPedagogyCollective]] – is at work (as of 2012) producing demonstrative material which will encourage and enable more people to learn this system. There have been two [[ThirtyOneToneSinginCamp]]s as well. | ||
* [[CG-31]] | * [[CG-31]] | ||
== Further reading == | == Further reading == | ||