Mothra: Difference between revisions
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{{Infobox | {{Interwiki | ||
| en = Mothra | |||
| de = Slendrisch #Mothra | |||
}} | |||
{{Infobox regtemp | |||
| Title = Mothra | | Title = Mothra | ||
| Subgroups = 2.3.5.7 | | Subgroups = 2.3.5.7 | ||
| Comma basis = [[81/80]], [[1029/1024]] | | Comma basis = [[81/80]], [[1029/1024]] | ||
| Edo join 1 = 26 | Edo join 2 = 31 | | Edo join 1 = 26 | Edo join 2 = 31 | ||
| Mapping = 1; 3 12 -1 | | Mapping = 1; 3 12 -1 | ||
| Generators = 8/7 | Generators tuning = 232.3 | Optimization method = CWE | |||
| MOS scales = [[1L 4s]], [[5L 1s]], [[5L 6s]], …, [[5L 21s]] | |||
| Pergen = (P8, P5/3) | | Pergen = (P8, P5/3) | ||
| Odd limit 1 = 7 | Mistuning 1 = | | Odd limit 1 = 7 | Mistuning 1 = 5.4 | Complexity 1 = 31 | ||
| Odd limit 2 = (2.3.5.7) 21 | Mistuning 2 = | | Odd limit 2 = (2.3.5.7) 21 | Mistuning 2 = 10.8 | Complexity 2 = 36 | ||
}} | }} | ||
'''Mothra''', also known as '''cynder''', is a temperament of the [[7-limit]] that is a strong extension to [[slendric]], which is defined by splitting a perfect fifth representing [[3/2]] into three intervals of [[8/7]], tempering out [[1029/1024]]. The fifth of mothra is flattened to a [[meantone]] fifth, so that it reaches [[5/4]] when stacked four times and [[81/80]] is tempered out, unlike that of the other slendric extension [[rodan]], which is sharpened from just. This has the effect of bringing the generator 8/7 considerably closer to just, and also allowing [[MOS scale]]s of mothra to be more melodically usable than those of other forms of slendric, as the structurally-pervasive small step known as the [[quark]] (the residue between the octave and 5 generators, representing [[49/48]], [[64/63]], and in mothra also [[36/35]]) is larger here. [[EDOs]] that support mothra include [[26edo]], [[31edo]], and [[36edo]], and 31 is a particularly good tuning. | |||
'''Mothra''' is a temperament | |||
In the [[11-limit]], two extensions are of note: undecimal mothra (26 & 31), which tempers out [[99/98]], [[385/384]] and [[441/440]] to find the 11th harmonic at 8 generators down, and mosura (31 & 36), which tempers out [[176/175]] to find the 11th harmonic at 23 generators up. These two mappings merge at 31edo, which is therefore a uniquely suitable tuning for 11-limit mothra. | In the [[11-limit]], two extensions are of note: undecimal mothra (26 & 31), which tempers out [[99/98]], [[385/384]] and [[441/440]] to find the 11th harmonic at 8 generators down, and mosura (31 & 36), which tempers out [[176/175]] to find the 11th harmonic at 23 generators up. These two mappings merge at 31edo, which is therefore a uniquely suitable tuning for 11-limit mothra. | ||
In higher limits, one may note that the two-generator interval closely approximates [[17/13]], and that the six-generator interval - the meantone whole tone of [[9/8]][[~]][[10/9]], approximates [[19/17]] | In higher limits, one may note that the two-generator interval closely approximates [[17/13]], and that the six-generator interval - the meantone whole tone of [[9/8]][[~]][[10/9]], approximates [[19/17]] - so that the 13:17:19 chord is well-represented; it is worth noting also that this chord is entirely included within the subtemperament obtained from taking every other generator of mothra, which is [[A-team]] (the crawma, [[83521/83486]], is the relevant comma tempered out here). This can be combined with the canonical mapping of 13 for each undecimal extension, which tempers out [[144/143]], to provide a natural route to the [[19-limit]]. | ||
For technical data, see [[Gamelismic clan #Mothra]]. | For technical data, see [[Gamelismic clan #Mothra]]. | ||
== Intervals == | == Intervals == | ||
As a strong extension of slendric, mothra's intervals can be expressed using the same system of extended diatonic interval naming [[Slendric#Interval categories|used for slendric]]. It is particularly convenient to use diatonic conventions for mothra, because its chain of fifths is meantone, and therefore 5/4 is simply read as a major third. | As a strong extension of slendric, mothra's intervals can be expressed using the same system of extended diatonic interval naming [[Slendric #Interval categories|used for slendric]]. It is particularly convenient to use diatonic conventions for mothra, because its chain of fifths is meantone, and therefore 5/4 is simply read as a major third. | ||
In the following table, odd harmonics and subharmonics 1–21 are labeled in '''bold'''. | In the following table, odd harmonics and subharmonics 1–21 are labeled in '''bold'''. | ||
{| class="wikitable sortable center- | {| class="wikitable sortable center-1 center-2 right-3" | ||
|- | |- | ||
! rowspan="3" | | ! rowspan="3" | # !! rowspan="3" | Extended <br> diatonic <br> interval !! rowspan="3" | Cents* !! colspan="3" | Approximate ratios | ||
|- | |- | ||
! rowspan="2" | 7-limit intervals !! colspan="2" | Intervals of | ! rowspan="2" | 7-limit intervals !! colspan="2" | Intervals of 11-limit extensions | ||
|- | |- | ||
! Undecimal mothra !! Mosura | ! Undecimal mothra !! Mosura | ||
| Line 222: | Line 225: | ||
| 33/32, 55/54 | | 33/32, 55/54 | ||
|} | |} | ||
<nowiki/>* In 7-limit [[CWE tuning]] | <nowiki/>* In 7-limit [[CWE tuning]], octave reduced | ||
== Tuning spectrum == | == Tunings == | ||
Vals refer to the appropriate undecimal extension in the | === Norm-based tunings === | ||
{| class="wikitable mw-collapsible mw-collapsed" | |||
|+ style="font-size: 105%; white-space: nowrap;" | 7-limit norm-based tunings | |||
|- | |||
! rowspan="2" | | |||
! colspan="3" | Euclidean | |||
|- | |||
! Constrained | |||
! Constrained & skewed | |||
! Destretched | |||
|- | |||
! Tenney | |||
| CTE: ~8/7 = 232.3996{{c}} | |||
| CWE: ~8/7 = 232.2514{{c}} | |||
| POTE: ~8/7 = 232.1933{{c}} | |||
|} | |||
=== Tuning spectrum === | |||
{{See also| Slendric #Tuning spectrum }} | |||
Vals refer to the appropriate undecimal extension in the edo's range. | |||
{| class="wikitable center-all left-4 left-5" | {| class="wikitable center-all left-4 left-5" | ||
| Line 329: | Line 352: | ||
| 232.193 | | 232.193 | ||
| | | | ||
| 1/4-comma meantone fifth, 5-odd-limit minimax | | 1/4-comma meantone fifth, (7-limit) 5- through 21-odd-limit minimax | ||
|- | |- | ||
| | | | ||
| Line 372: | Line 395: | ||
| | | | ||
| | | | ||
|- | |- | ||
| [[67edo|13\67]] | | [[67edo|13\67]] | ||
| Line 424: | Line 441: | ||
== Music == | == Music == | ||
[http://micro.soonlabel.com/16-ET/mothra/20141028_mothra16br4.mp3 | ; [[Chris Vaisvil]] | ||
* ''Prelude for solo piano'' (2014) by [[Chris Vaisvil]] – [https://web.archive.org/web/20201127013310/http://micro.soonlabel.com/16-ET/mothra/20141028_mothra16br4.mp3 play] | [https://www.chrisvaisvil.com/prelude-for-solo-piano-in-mothra16-brat-4-tuning/ blog] – in Mothra[16], brat 4 tuning | |||
[[Category:Mothra| ]] <!-- main article --> | [[Category:Mothra| ]] <!-- main article --> | ||