Rastmic clan: Difference between revisions

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- CTE & POTE tunings
Another pass on neutrality, explaining what actually happens with CTE/CWE and giving an alternative that bypasses their mechanics
 
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=== Namo ===
=== Namo ===
Namo adds [[144/143]] to the comma list and finds ~[[16/13]] at the same neutral third. With 11/9~16/13, it requires a slightly flat ~[[27/22]] as the tuning of the neutral third. [[58edo]] is the largest [[patent val]] tuning for it in the [[optimal ET sequence]], with a tuning between that of [[17edo]] and [[41edo]], so that ~11 and ~13 are practically equally sharp, given that [[29edo]] forms a [[consistent circle]] of [[13/11]]'s with a [[closing error]] of 31.2%. It might be recommended as a tuning for this reason, as having the neutral third much sharper to optimize plausibility of ~16/13 implies that the 11 is extremely sharp because 11/9 must be tuned sharp so that 11 must be sharper than 9, which is thus four times as sharp as however sharp of the (3/2)<sup>1/2</sup> neutral third is, while tuning it much flatter means that you increase the error of 16/13, which in 58edo is already as almost 8{{cent}} off and in [[99edo|99ef]] it is only slightly worse. For these reasons, Godtone is not fond of the recommendations by the various [[optimal tuning]]s to tune flat of 58edo, although it is clear that in an optimal tuning nothing much sharper than 58edo should be used, as making 11 more off than 13 would imply damaging 3 and 11/9 more than necessary. Curiously, [[POTE]] (351.488{{c}}) recommends a sharper tuning than [[CWE]] here, but still flat of 58edo.
Namo adds [[144/143]] to the comma list and finds ~[[16/13]] at the same neutral third. With 11/9~16/13, it requires a slightly flat ~[[27/22]] as the tuning of the neutral third. [[58edo]] is the largest [[patent val]] tuning for it in the [[optimal ET sequence]], with a tuning between that of [[17edo]] and [[41edo]], so that ~11 and ~13 are practically equally sharp, given that [[29edo]] forms a [[consistent circle]] of [[13/11]]'s with a [[closing error]] of 31.2%. It might be recommended as a tuning for this reason, as having the neutral third tuned much sharper to optimize the plausibility of prime 13 implies that the 11 is extremely sharp because 11/9 must be tuned sharp so that 11 must be sharper than 9, which is four times as sharp as however sharp of just the (3/2)<sup>1/2</sup> neutral third is, while tuning it much flatter means increasing the error of prime 13, which in 58edo is already almost 8{{cent}} off and in [[99edo|99ef-edo]] it is only slightly worse.  
 
The [[CWE]] tuning given below takes account of how optimizational resource is best used. As such, the optimum is not raised much in the introduction of prime 13, as each unit increment in the generator implies four and five times more error in the harmonics 9 and 11, respectively, damaging them more than necessary. A sharper pure-octave tuning would be given by CTOP (~351.7142{{c}}), which is still flat of 58edo.


[[Subgroup]]: 2.3.11.13
[[Subgroup]]: 2.3.11.13

Latest revision as of 16:07, 24 August 2025

This is a list showing technical temperament data. For an explanation of what information is shown here, you may look at the technical data guide for regular temperaments.

The rastmic clan of temperaments tempers out the rastma, 243/242 ([-1 5 0 0 -2).

Neutral

Neutral is the 2.3.11-subgroup temperament with a generator of a neutral third which can be taken to represent 11/9~27/22, two of which make up a perfect fifth of 3/2. It can be thought of as the 2.3.11 version of either mohajira or neutrominant, as well as suhajira and ringo. Among other things, it is the temperament optimizing the neutral tetrad.

Subgroup: 2.3.11

Comma list: 243/242

Subgroup-val mapping[1 1 2], 0 2 5]]

Gencom mapping[1 1 0 0 2], 0 2 0 0 5]]

mapping generators: ~2, ~11/9

Optimal tunings:

  • WE: ~2 = 1200.0635 ¢, ~11/9 = 350.5439 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 350.5486 ¢

Optimal ET sequence7, 17, 24, 65, 89, 202, 291, 380

Badness (Sintel): 0.0700

Scales: neutral7, neutral10, neutral17

Namo

Namo adds 144/143 to the comma list and finds ~16/13 at the same neutral third. With 11/9~16/13, it requires a slightly flat ~27/22 as the tuning of the neutral third. 58edo is the largest patent val tuning for it in the optimal ET sequence, with a tuning between that of 17edo and 41edo, so that ~11 and ~13 are practically equally sharp, given that 29edo forms a consistent circle of 13/11's with a closing error of 31.2%. It might be recommended as a tuning for this reason, as having the neutral third tuned much sharper to optimize the plausibility of prime 13 implies that the 11 is extremely sharp because 11/9 must be tuned sharp so that 11 must be sharper than 9, which is four times as sharp as however sharp of just the (3/2)1/2 neutral third is, while tuning it much flatter means increasing the error of prime 13, which in 58edo is already almost 8 ¢ off and in 99ef-edo it is only slightly worse.

The CWE tuning given below takes account of how optimizational resource is best used. As such, the optimum is not raised much in the introduction of prime 13, as each unit increment in the generator implies four and five times more error in the harmonics 9 and 11, respectively, damaging them more than necessary. A sharper pure-octave tuning would be given by CTOP (~351.7142 ¢), which is still flat of 58edo.

Subgroup: 2.3.11.13

Comma list: 144/143, 243/242

Subgroup-val mapping[1 1 2 4], 0 2 5 -1]]

Gencom mapping[1 1 0 0 2 4], 0 2 0 0 5 -1]]

Optimal tunings:

  • WE: ~2 = 1198.8553 ¢, ~11/9 = 351.1523 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 351.2700 ¢

Optimal ET sequence7, 10, 17, 41, 58, 99ef, 239eefff, 338eeeffff

Badness (Sintel): 0.133

Suhajira

Subgroup: 2.3.7.11

Comma list: 64/63, 243/242

Subgroup-val mapping[1 1 4 2], 0 2 -4 5]]

Gencom mapping[1 1 0 4 2], 0 2 0 -4 5]]

Optimal tunings:

  • WE: ~2 = 1196.3496 ¢, ~11/9 = 352.8809 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 353.7832 ¢

Optimal ET sequence7, 10, 17, 44e, 61de, 78ddee, 139bdddeeee

Badness (Sintel): 0.602

Scales: suhajira7, suhajira10, suhajira17

2.3.7.11.13 subgroup

Subgroup: 2.3.7.11.13

Comma list: 64/63, 78/77, 144/143

Subgroup-val mapping: [1 1 4 2 4], 0 2 -4 5 -1]]

Gencom mapping: [1 1 0 4 2 4], 0 2 0 -4 5 -1]]

Optimal tunings:

  • WE: ~2 = 1196.8114 ¢, ~11/9 = 352.8351 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 353.6791 ¢

Optimal ET sequence: 7, 10, 17, 44e, 61de, 78ddee

Badness (Sintel): 0.425

Scales: suhajira7, suhajira10, suhajira17

Mohaha

Mohaha can be thought of, intuitively, as meantone with quartertones; as is the 3/2 generator subdivided in half, so is the ~25/24 chromatic semitone divided into two equal ~33/32 quartertones (in the 2.3.5.11 subgroup). Within this paradigm, mohaha is the temperament that splits the 3/2 into two equal 11/9's, that splits the 6/5 into two equal 11/10~12/11's, and that maps four 3/2's to 5/1. It has a heptatonic mos with three larger steps and four smaller ones, going sLsLsLs. Taking septimal meantone mapping of 7 leads to #Migration, flattone mapping of 7 leads to #Ptolemy, and dominant mapping of 7 leads to #Neutrominant, while tempering out 176/175 gives mohajira (shown at Meantone family).

2.3.5.11 subgroup

The S-expression-based comma list of this temperament is {S6/S8 = S9, S11}.

Subgroup: 2.3.5.11

Comma list: 81/80, 121/120

Subgroup-val mapping[1 1 0 2], 0 2 8 5]]

Gencom mapping[1 1 0 0 2], 0 2 8 0 5]]

Optimal tunings:

  • WE: ~2 = 1201.8548 ¢, ~11/9 = 348.6318 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 348.3793 ¢

Optimal ET sequence7, 17c, 24, 31, 69e, 100e, 131bee

Badness (Sintel): 0.401

Scales: mohaha7, mohaha10

Mohoho

Subgroup: 2.3.5.11.13

Comma list: 66/65, 81/80, 121/120

Subgroup-val mapping: [1 1 0 2 4], 0 2 8 5 -1]]

Gencom mapping: [1 1 0 0 2 4], 0 2 8 0 5 -1]]

Optimal tunings:

  • WE: ~2 = 1199.8846 ¢, ~11/9 = 348.8820 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 348.9040 ¢

Optimal ET sequence: 7, 17c, 24, 31, 55

Badness (Sintel): 0.401

Scales: mohaha7, mohaha10

Migration

Subgroup: 2.3.5.7.11

Comma list: 81/80, 121/120, 126/125

Mapping: [1 1 0 -3 2], 0 2 8 20 5]]

Optimal tunings:

  • WE: ~2 = 1201.7423 ¢, ~11/9 = 348.6879 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 348.2867 ¢

Optimal ET sequence: 7d, 24d, 31, 100de, 131bdee, 162bdee

Badness (Sintel): 0.844

13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 66/65, 81/80, 121/120, 126/125

Mapping: [1 1 0 -3 2 4], 0 2 8 20 5 -1]]

Optimal tunings:

  • WE: ~2 = 1200.2590 ¢, ~11/9 = 348.5648 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 348.5009 ¢

Optimal ET sequence: 7d, 24d, 31

Badness (Sintel): 1.16

Ptolemy

"Ptolemy" redirects here. For the Ancient Greek polymath, see Wikipedia: Ptolemy.

Subgroup: 2.3.5.7.11

Comma list: 81/80, 121/120, 525/512

Mapping: [1 1 0 8 2], 0 2 8 -18 5]]

Optimal tunings:

  • WE: ~2 = 1203.8812 ¢, ~11/9 = 348.0444 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 346.9194 ¢

Optimal ET sequence: 7, 31dd, 38d, 45e, 83bcddee

Badness (Sintel): 1.94

13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 65/64, 81/80, 105/104, 121/120

Mapping: [1 1 0 8 2 6], 0 2 8 -18 5 -8]]

Optimal tunings:

  • WE: ~2 = 1203.9456 ¢, ~11/9 = 348.0510 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 346.8878 ¢

Optimal ET sequence: 7, 31ddf, 38df, 45ef, 83bcddeeff, 128bccddeeefff

Badness (Sintel): 1.42

Neutrominant

The neutrominant temperament (formerly maqamic temperament) has a hemififth generator (~11/9) and tempers out 36/35 and 121/120. It makes the most sense if viewed as an adaptive temperament, whereby 7/4 and 9/5 simply share an equivalence class in the resulting scales, but don't need to share a particular tempered "middle-of-the-road" intonation.

Subgroup: 2.3.5.7.11

Comma list: 36/35, 64/63, 121/120

Mapping: [1 1 0 4 2], 0 2 8 -4 5]]

Optimal tunings:

  • WE: ~2 = 1195.9529 ¢, ~11/9 = 349.7505 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 350.7031 ¢

Optimal ET sequence: 7, 17c, 24d, 41cd

Badness (Sintel): 1.33

13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 36/35, 64/63, 66/65, 121/120

Mapping: [1 1 0 4 2 4], 0 2 8 -4 5 -1]]

Optimal tunings:

  • WE: ~2 = 1196.3143 ¢, ~11/9 = 349.7387 ¢
  • CWE: ~2 = 1200.0000 ¢, ~11/9 = 350.6573 ¢

Optimal ET sequence: 7, 17c, 24d, 41cd

Badness (Sintel): 1.12

Semisema

In addition to dividing the perfect fifth into two equal parts of 11/9~27/22, semisema, being an extension of semaphore, also divides the perfect fourth into two equal parts of 7/6~8/7.

Subgroup: 2.3.7.11

Comma list: 49/48, 243/242

Subgroup-val mapping[2 0 4 -1], 0 2 1 5]]

Gencom mapping[2 0 0 4 -1], 0 2 0 1 5]]

mapping generators: ~77/54, ~7/4

Optimal tunings:

  • WE: ~2 = 601.5167 ¢, ~7/4 = 951.1267 ¢
  • CWE: ~2 = 600.0000 ¢, ~7/4 = 949.6883 ¢

Optimal ET sequence10, 14, 24, 62dd

Badness (Sintel): 0.776