Xenharmonic Wiki

User:Eliora/Concoctic scale: Difference between revisions

← Older edit
VisualWikitext
Eliora (talk | contribs)
autopatrolled, emailconfirmed
3,387 edits
BudjarnLambeth (talk | contribs)
autopatrolled, emailconfirmed
21,276 edits
mNo edit summary
 
(24 intermediate revisions by 7 users not shown)
Line 1: Line 1:
Concoctic scale (name proposed by Eliora) is a [[Maximal evenness|maximum eveness]] scale which has the same number of notes as its MOS generator.
{{Editable user page}}
A '''concoctic scale''' (name proposed by Eliora) is a [[maximally even]] scale which has the same number of notes as its MOS [[generator]].


12edo 5L2s diatonic scale, the predominantly used scale in the world today, is an example of such a scale.
12edo 5L2s diatonic scale, the predominantly used scale in the world's music today, is an example.


== Mathematical definition ==
== Mathematical derivation ==
The length of a maximum evenness scale's generator can be determined through a '''modular multiplicative inverse''' of the note amount and the tuning size<ref>https://individual.utoronto.ca/kalendis/leap/index.htm</ref>:
The length of a maximally even scale's generator can be determined through a '''modular multiplicative inverse''' of the note amount and the tuning size<ref>https://individual.utoronto.ca/kalendis/leap/index.htm</ref>.


<math>ax \equiv 1\mod N</math>,
<math>ax \equiv 1\mod N</math>,
Line 16: Line 17:
<math>a^2 \equiv 1\mod N \hspace{4cm} (1)</math>.
<math>a^2 \equiv 1\mod N \hspace{4cm} (1)</math>.


There are also paraconcoctic scales, or chroma-negative concoctic scales. The formula for such a scale is  
A scale is called '''orthoconcoctic''', if the generator corresponding to note amount is the chroma-positive generator, for example - the 12edo diatonic scale is. There are also '''paraconcoctic''' scales, or chroma-negative concoctic scales. The formula for such a scale is  


<math>a^2 \equiv -1\mod N \hspace{4cm} (2)</math>.
<math>a^2 \equiv -1\mod N \hspace{4cm} (2)</math>.


Since octave-inverting the MOS generator has no impact on the scale, paraconcoctic scales are identical to their usual, orthoconcoctic counterparts. However, the difference is pronounced in keyboard making - in terms of chroma direction, the white keys' generator will be the amount of black keys and vice versa.  
Since octave-inverting the MOS generator has no impact on the scale, paraconcoctic scales are identical to their usual, orthoconcoctic counterparts. However, the difference is pronounced in terms of modal brightness.  


=== Example ===
=== Example ===
12edo keyboard layout predominantly in use in the world today features 7 white keys and 5 black keys. In direction-conscious manner, the diatonic scale of 7 keys is obtained by stacking the generator, 7\12 fifth 7 times. Likewise, the pentatonic of black keys is obtained by stacking the 5\12 perfect fourth 5 times. And such scale is generated with the first formula.
12edo keyboard layout predominantly in use in the world today features 7 white keys and 5 black keys. In direction-conscious manner, the diatonic scale of 7 keys is obtained by stacking the generator, 7\12 fifth 7 times. Likewise, the pentatonic of black keys is obtained by stacking the 5\12 perfect fourth 5 times. And such scale is generated with the first formula.


On the other hand, in [[25edo]], stacking 18\25 will lead to maximum evenness scale of 7 note "black keys", and stacking 7\25 will result in a 18-note scale of "white keys". This is the EDO that only has the scale through the second formula.
On the other hand, in [[25edo]], stacking 18\25 will lead to maximally even scale of 7 note "black keys", and stacking 7\25 will result in a 18-note scale of "white keys". This is the EDO that only has the scale through the second formula.


=== Observations ===
=== Observations ===
Line 41: Line 42:


Therefore the remainder of +1 means that such a scale will always be orthoconcoctic. This type of scale, when used in keyboard making, produces two bundles of white keys whose numbers of black keys inside of them are 1 number apart, and so are the numbers of white keys themselves. The sequence goes as follows: 5\8, 7\12, 9\16, 11\20, etc.
Therefore the remainder of +1 means that such a scale will always be orthoconcoctic. This type of scale, when used in keyboard making, produces two bundles of white keys whose numbers of black keys inside of them are 1 number apart, and so are the numbers of white keys themselves. The sequence goes as follows: 5\8, 7\12, 9\16, 11\20, etc.
=== Temperaments ===
Since maximal evenness scales can be used to generate a temperament by merging the note count in the period and the period cardinality, in this case being 1 octave, an array of concoctic temperaments can be defined through such mergers. For example, temperament taken this way from 12edo, 7 & 12, is meantone, and is predominantly in use in the world's music today.
In addition, this also means that every concoctic scale has a 5-limit comma attached to it, and also an infinite array of 3-number subgroup commas.


== List ==
== List ==
The sequence of EDOs which have concoctic scales of any kind appears to be [[oeis:A172019|A172019]]. This implies that in order for an EDO to have a concoctic scale, it's number of coprime distinct generators must be divisible by 4. The reason for this is yet to be investigated.
The sequence of EDOs which have concoctic scales of any kind appears to be [[oeis:A172019|A172019]]. This implies that in order for an EDO to have a concoctic scale, it's number of coprime distinct generators must be divisible by 4. The reason for this is yet to be investigated.


The sequence has the asymptotic density 1, meaning that as EDOs grow increasingly large, they are significantly more likely to have a concoctic scale than not to.
The sequence has the asymptotic density 1, meaning that as EDOs grow increasingly large, they are significantly more likely to have a concoctic scale than not to. As a result, it may be better to refer to [[oeis:A097987|A097987]], a set of numbers which lack a concoctic scale.
 
=== Concoctic scales in EDOs ===
Notation: c.II means contorted order 2, etc for other Roman numerals.
{| class="wikitable"
{| class="wikitable"
|+
|+
Non-trivial concoctic scales (above 1\2) in EDOs up to 100 that have them
Non-trivial concoctic scales in EDOs up to 100 that have them
!N
! rowspan="2" |N
!Scale
! rowspan="2" |Scale\EDO
!Mos
! colspan="2" |MOS
(chroma+)
! colspan="2" |Generator Size (cents)
!Mos
! rowspan="2" |Associated
(chroma-)
5-limit comma
!Generator Size (cents)
! rowspan="2" |Associated
other commas
!Notes
!Notes
|-
!Chroma+
!Chroma-
!Below 1\2
!Above 1\2
!
|-
|-
|5
|5
Line 62: Line 78:
|
|
|
|
|480
|720
|720
|[[16/15]]
|
|
|
|-
|-
Line 69: Line 88:
|[[3L 2s]]
|[[3L 2s]]
|2L 1s
|2L 1s
|450
|750
|750
|16/15
|
|
|Forms the [[Father]].
|-
|-
|10
|10
Line 76: Line 98:
|2L 1s
|2L 1s
|[[3L 4s]]
|[[3L 4s]]
|360
|840
|840
|[[25/24]]
|
|
|Forms the [[Dicot]].
|-
|-
|12
|12
Line 83: Line 108:
|[[5L 2s]]
|[[5L 2s]]
|[[2L 3s]]
|[[2L 3s]]
|500
|700
|700
|[[81/80]]
|
|The scale predominantly in use in the world today.
|The scale predominantly in use in the world today.
|-
|-
Line 90: Line 118:
|[[3L 2s]]
|[[3L 2s]]
|[[5L 3s]]
|[[5L 3s]]
|
|738.461538
|738.461538
|[[2560/2187]]
|
|Forms the [[Oneirotonic]] scale.
|Forms the [[Oneirotonic]] scale.
|-
|-
Line 97: Line 128:
|[[Tetrad 3L 1s|4L 7s]]
|[[Tetrad 3L 1s|4L 7s]]
|[[Tetrad 3L 1s|3L 1s]]
|[[Tetrad 3L 1s|3L 1s]]
|
|880
|880
|Forms the [[Hanson]].
|[[15625/15552]]*
|
|*Forms the [[Hanson]] (11b & 15)
|-
|-
|16
|16
Line 104: Line 138:
|[[7L 2s]]
|[[7L 2s]]
|[[2L 5s]]
|[[2L 5s]]
|
|675
|675
|[[135/128]]
|
|Forms the [[Mavila]].
|Forms the [[Mavila]].
|-
|-
Line 111: Line 148:
|[[1L 3s]]
|[[1L 3s]]
|[[4L 9s]]
|[[4L 9s]]
|
|917.647059
|917.647059
|[[25/24]] c.II
|
|
|Forms [[Lovecraft]], [[Huxley]] and [[Subklei]], but with a fair error.
|-
|-
|20
|20
Line 118: Line 158:
|[[9L 2s]]
|[[9L 2s]]
|[[2L 7s]]
|[[2L 7s]]
|
|660
|660
|[[34171875/33554432|[-25, 7, 6⟩]] c.II
|
|
|
|-
|-
|21
|21
|13\21
|13\21
|
|
|
|
|
|742.857143
|742.857143
|[39, -7, -12⟩
|
|
|
|-
|-
|24
|24
|13\24, 17\24, 19\24
|13\24, 17\24, 19\24
|
|
|
|
|
|650, 850, 950
|650, 850, 950
|262144/253125 c.II,
32805/32768 c.II,
[[Godzilla|81/80 c.II]]
|
|
|Contorted [[Passion]], contorted [[Helmholtz (temperament)|Helmholtz]] and [[Godzilla]].
|-
|-
|25
|25
|18\25
|18\25
|
|
|
|
|
|864
|864
|3125/2916
|
|
|Forms the [[Sixix]].
|-
|-
|26
|26
|21\26
|21\26
|[[1L 4s]]
|[[5L 16s]]
|
|
|
|
|[<nowiki/>[[597871125/536870912|-29, 14, 3]]⟩
|
|
|Forms the slendric pentad.
|The 5-note scale itself is the [[slendric pentad]].
|-
|-
|28
|28
Line 153: Line 211:
|
|
|
|
|
|
|[20, 5, -12⟩
|
|
|
|
Line 162: Line 223:
|
|
|
|
|[[32805/32768]]
|
|Forms the [[Helmholtz (temperament)|Helmholtz]].
|-
|-
|30
|30
Line 167: Line 231:
|
|
|
|
|
|
|15625/15552 c.II
|
|
|
|
Line 176: Line 243:
|
|
|
|
|64000/59049
|
|Forms the [[Satriyo]].
|-
|-
|33
|33
Line 181: Line 251:
|
|
|
|
|
|
|177147/160000 c.II
|
|
|
|
Line 188: Line 261:
|
|
|
|
|
|
|[39, -7, -12⟩
|
|
|
|
Line 195: Line 271:
|
|
|
|
|
|
|[-41, 4, 15⟩
|
|
|
|
Line 202: Line 281:
|
|
|
|
|
|
|81/80 c.III
|2.3.7 [[177147/175616]]
|In the 2.3.7, forms [[Liese]].
|-
|37
|31\37
|
|
|
|
|393216/390625 c.II
|
|
|-
|39
|25\39
|
|
|
|
|[44, -13, -10⟩
|
|
|-
|40
|21\40, 29\40, 31\40
|
|
|
|
|273375/262144,
[-57, 17, 13⟩,
[[Orson|[-21, 3, 7⟩]]
|
|31\40 forms the [[Orwell]] or [[Orson]].
|-
|41
|32\41
|
|
|
|
|[-35, 6, 11⟩
|
|
|
|
Line 210: Line 336:
|
|
|
|
|One step short of 53edo's perfect fifth.
|
|15625/15552 c.IV
|
|One step short of [[53edo]]'s perfect fifth.
|-
|55
|34\55
|
|
|
|
|[39, -7, -12⟩
|
|
|-
|69
|22\69
|
|
|
|
|[-41, 1, 17⟩
|
|
|-
|72
|37\72, 53\72, 55\72
|
|
|
|
|
|
|53\72 forms the [[Catakleismic]].
|-
|80
|41\80, 49\80
|
|
|
|735
|
|
|49\80 forms the [[Semisept]].
|-
|-
|84
|84
|71\84
|71\84
|58L 13s
|58L 13s
|
|
|
|1014.285714
|1014.285714
|
|
|
|
|-
|-
Line 222: Line 394:
|64\91
|64\91
|37L 27s
|37L 27s
|
|
|
|843.956043
|843.956043
|
|
|
|-
|93
|61\93
|
|
|
|
|
|
|
|-
|100
|51\100
|
|
|
|
|
|
|
|}
=== Concoctic scales by note count ===
{| class="wikitable"
|+Concoctic scales sorted by note count in MOSes that have them
!N
!MOS (chroma+)
!Generator
!Cents
|-
| rowspan="5" |7
|1L 6s
|
|
|-
|2L 5s
|7\16
|
|-
|3L 4s
|7\10
|
|-
|5L 2s
|7\12
|
|-
|6L 1s
|
|
|
|}
|}
Line 229: Line 454:
== References ==
== References ==


[[Category:Scale theory]]
[[Category:Scale]]
Retrieved from "https://en.xen.wiki/w/User:Eliora/Concoctic_scale"