Pentadacus: Difference between revisions

CompactStar (talk | contribs)
No edit summary
CompactStar (talk | contribs)
No edit summary
Line 3: Line 3:
| Subgroups = 5.7.11
| Subgroups = 5.7.11
| Comma basis = [[831875/823543]]
| Comma basis = [[831875/823543]]
| Edo join 1 = 14ed5 | Edo join 2 = 15ed5
| Edo join 1 = 43ed5 | Edo join 2 = 14ed5
| Mapping = 1; 3 7
| Mapping = 1; 3 7
| Generators = 55/49
| Generators = 55/49
| Generators tuning = 194.820
| Generators tuning = 194.820
| Optimization method = CWE
| Optimization method = CWE
| MOS scales = [[1L 1s (1/1-equivalent)|1L 1s<5/1>]], [[2L 1s (1/1-equivalent)|2L 1s<5/1>]],...,[[12L 1s (1/1-equivalent)|12L 1s<5/1>]], [[13L 1s (1/1-equivalent)|13L 1s<5/1>]],
| MOS scales = [[1L 11s (1/1-equivalent)|1L 13s<5/1>]], [[1L 12s (5/1-equivalent)|1L 12s<5/1>]], [[1L 13s (1/1-equivalent)|1L 13s<5/1>]], [[14L 1s (1/1-equivalent)|14L 1s<5/1>]], [[1L 13s (1/1-equivalent)|1L 13s<5/1>]]
| Color name =  
| Color name =  
}}
Pentadacus is a [[nonoctave]] [[regular temperament]] in the 5.7.11 [[subgroup]] which tempers out the comma [[831875/823543]]. It is even more exotic than [[Bohlen-Pierce]], lacking both [[2/1]] and [[3/1]], and typically it would be used with an [[equave]] of [[5/1]]. It is generated by a [[meantone]]-esque small whole tone interval that represents [[54/49]]. Stacking 3 of these tones gives [[7/5]] and 7 of them give [[11/5]]. Pentadacus has both low [[complexity]] (especially by the standards of the 5/1-equivalent world, where scales have lots of notes) and low [[error]] if tuned correctly, providing an [[efficiency|efficient]] traversal of the 5.7.11 subgroup. It was discovered by CompactStar in 2026.
[[14ed5]] is an inaccurate but important tuning of Pentadacus, because in 14ed5, the whole tone generator corresponds to a single step of 14ed5, although the whole tone is bigger than usual being around [[9/8]]-sized, causing the approximations of 7/5 and 11/5 to be bad. Basically, pentadacus can be thought of as a compressed 14ed5, at least until you hit [[5/1]]. 14ed5 is also close to [[6edo]], the familiar whole-tone scale with octaves, and 6 generators in pentadacus can sound like a tempered octave but it’s usually bad enough to be dissonant.
Pentadacus is connected to the octave-repeating [[didacus]] temperament as both have a small whole tone generator for which 3 stack to 7/5, and 11-limit didacus is actually a weak extension of pentadacus to include octaves.
[[Category:Rank-2 temperaments]]
| Edo join 1 = [[13ed5|c13]] | Edo join 2 = b88
| Mapping = 1; -5 -4
| Generators = 7/5
| Generators tuning = 583.986
| Optimization method = CWE
| MOS scales = [[3L 1s (3/1-equivalent)|3L 1s <3/1>]], [[3L 4s (3/1-equivalent)|3L 4s <3/1>]], [[3L 7s (3/1-equivalent)|3L 7s <3/1>]]
| Color name =
| Odd limit 1 = 3.5.7 7 | Mistuning 1 = 1.40 | Complexity 1 = 7
| Odd limit 2 = 3.5.7 49 | Mistuning 2 = 2.80 | Complexity 2 = 13
}}
}}