Quasisuper
Lua error in Module:Infobox_regtemp at line 138: attempt to perform arithmetic on local 'generator_size' (a nil value). Quasisuper is an alternative extension of the archy chain of fifths to superpyth. Like superpyth, it is a temperament generated by a perfect fifth, where stacking two of them reaches the interval of 8/7~9/8, tempering out 64/63. The difference is that this extension maps prime 5 to -13 generators, as a double-diminished fifth (C–G𝄫). This extension works in the range 17c-edo to 22-edo. In contrast, full 7-limit superpyth does not work in this range, as tunings with a flatter fifth than 22edo swap the sizes of 7/5 and 10/7. This extension may be preferred over superpyth due to having a softer diatonic scale, with a small step of around 60 cents compared to about 50 cents in regular 7-limit superpyth.
The best extension to the 11-limit, quasisupra, uses the supra mapping of prime 11 to -6 generators, as a diminished fifth (C–G♭). This tempers out 99/98 as in supra, as well as 121/120 and 540/539.
For technical data see Archytas clan #Quasisuper.
Interval chain
In the following table, odd harmonics and subharmonics 1–11 are in bold.
| # | Cents* | Approximate ratios |
|---|---|---|
| 0 | 0.0 | 1/1 |
| 1 | 708.3 | 3/2 |
| 2 | 216.6 | 8/7, 9/8 |
| 3 | 925.0 | 12/7 |
| 4 | 433.3 | 9/7, 14/11 |
| 5 | 1141.6 | 21/11, 27/14 |
| 6 | 649.9 | 16/11, 22/15 |
| 7 | 158.2 | 11/10, 12/11 |
| 8 | 866.6 | 18/11 |
| 9 | 374.9 | 27/22, 56/45 |
| 10 | 1083.2 | 28/15 |
| 11 | 591.5 | 7/5 |
| 12 | 99.8 | 16/15 |
| 13 | 808.2 | 8/5 |
| 14 | 316.5 | 6/5 |
| 15 | 1024.8 | 9/5 |
| 16 | 533.1 | 27/20 |
| 17 | 41.4 | 81/80, 56/55 |
* in 11-limit CWE tuning, octave reduced
Tunings
| Euclidean | |||
|---|---|---|---|
| Constrained | Constrained & skewed | Destretched | |
| Tenney | CTE: ~3/2 = 708.7690 ¢ | CWE: ~3/2 = 708.3716 ¢ | POTE: ~3/2 = 708.2385 ¢ |
| Euclidean | |||
|---|---|---|---|
| Constrained | Constrained & skewed | Destretched | |
| Tenney | CTE: ~3/2 = 708.7131 ¢ | CWE: ~3/2 = 708.3200 ¢ | POTE: ~3/2 = 708.2046 ¢ |