Mystery comma: Difference between revisions

From Xenharmonic Wiki
Jump to navigation Jump to search
Xenllium (talk | contribs)
No edit summary
Aura (talk | contribs)
No edit summary
 
(15 intermediate revisions by 7 users not shown)
Line 1: Line 1:
{{Infobox Interval
{{Infobox Interval
| Icon =
| Ratio = 70368744177664/68630377364883
| Ratio = 70368744177664 / 68630377364883
| Name = mystery comma, 29-comma, Pythagorean quadruple-diminished fourth, Pythagorean tridietic semilimma
| Monzo = 46 -29
| Color name = Wa-29, s<sup>4</sup>w4
| Cents = 43.30497
| Comma = yes
| Name = 29-comma, <br>29-3-comma
| Color name = s<sup>4</sup>w4
| FJS name =
| Sound =  
}}
}}
{{monzo|46 -29}}, the '''29-comma''' of 43.305 cents, is the difference between 46 octaves and 29 fifths, in other words 2<sup>46</sup>/3<sup>29</sup>. For EDOs up to 400, the 29-comma is tempered out if and only if 29 divides it, for example [[29edo]], [[58edo]] or [[87edo]].  
'''{{monzo|46 -29}}''', the '''mystery comma''' or '''29-comma''' of 43.305 cents, is the difference between 46 octaves and 29 fifths, in other words 2<sup>46</sup>/3<sup>29</sup>. When treated as an interval in its own right, there are actually two very good descriptive names for this interval.  Firstly, and most obviously, it can be called the '''Pythagorean quadruple-diminished fourth''', however, because it is also almost exactly half of the traditional [[Pythagorean limma]] (a stack of two mystery commas differing from the limma by [[Mercator's comma]]) in addition to being displaced from the unison's scale degree by three, one can also call this interval the '''Pythagorean tridietic semilimma'''.


== Temperaments ==
== Temperaments ==
Tempering out the 29-comma splits the octave into 29 equal parts and maps the harmonic 3 to 17\29. It leads to a number of regular temperaments including [[Hemifamity temperaments|mystery]].  
Tempering out this comma splits the octave into 29 equal parts and maps the harmonic 3 to 17\29, leading to the 5-limit version of [[Mystery|mystery temperament]]. For EDOs up to 400, the 29-comma is tempered out if and only if 29 divides it, for example [[29edo]], [[58edo]] or [[87edo]].  
 
=== 29-commatic (58&amp;87) ===
Subgroup: 2.3.5
 
[[Comma list]]: {{monzo|46 -29}}
 
[[Mapping]]: [{{val| 29 46 0 }}, {{val| 0 0 1 }}]
 
Mapping generators: ~531441/524288, ~5
 
[[POTE generator]]: ~5/4 = 387.408
 
{{Val list|legend=1| 29, 58, 87, 232, 319 }}
 
[[Badness]]: 1.020556
 
=== 7-limit 58&amp;87 ===
Subgroup: 2.3.5.7
 
[[Comma list]]: 5120/5103, 50421/50000
 
[[Mapping]]: [{{val| 29 46 0 14 }}, {{val| 0 0 1 1 }}]
 
[[POTE generator]]: ~5/4 = 388.646
 
{{Val list|legend=1| 29, 58, 87, 145 }}
 
[[Badness]]: 0.103734
 
=== 11-limit 58&amp;87 (Mystery) ===
Subgroup: 2.3.5.7.11
 
Comma list: 441/440, 896/891, 3388/3375
 
Mapping: [{{val| 29 46 0 14 33 }}, {{val| 0 0 1 1 1 }}]
 
POTE generator: ~5/4 = 388.460
 
Vals: {{Val list| 29, 58, 87, 145 }}
 
Badness: 0.034291


== See also ==
== See also ==
* [[Gallery of Just Intervals]]
* [[Medium comma]]
* [[Medium commas]]
* [[29th-octave temperaments]]


[[Category:3-limit]]
[[Category:29edo]]
[[Category:29edo]]
[[Category:Medium comma]]
[[Category:Mystery]]
[[Category:Commas with unknown etymology]]

Latest revision as of 01:26, 29 January 2025

Interval information
Ratio 70368744177664/68630377364883
Factorization 246 × 3-29
Monzo [46 -29
Size in cents 43.30497¢
Names mystery comma,
29-comma,
Pythagorean quadruple-diminished fourth,
Pythagorean tridietic semilimma
Color name Wa-29, s4w4
FJS name [math]\displaystyle{ \text{dddd4} }[/math]
Special properties reduced,
reduced subharmonic
Tenney height (log2 nd) 91.9639
Weil height (log2 max(n, d)) 92
Wilson height (sopfr(nd)) 179
Comma size medium
Open this interval in xen-calc

[46 -29, the mystery comma or 29-comma of 43.305 cents, is the difference between 46 octaves and 29 fifths, in other words 246/329. When treated as an interval in its own right, there are actually two very good descriptive names for this interval. Firstly, and most obviously, it can be called the Pythagorean quadruple-diminished fourth, however, because it is also almost exactly half of the traditional Pythagorean limma (a stack of two mystery commas differing from the limma by Mercator's comma) in addition to being displaced from the unison's scale degree by three, one can also call this interval the Pythagorean tridietic semilimma.

Temperaments

Tempering out this comma splits the octave into 29 equal parts and maps the harmonic 3 to 17\29, leading to the 5-limit version of mystery temperament. For EDOs up to 400, the 29-comma is tempered out if and only if 29 divides it, for example 29edo, 58edo or 87edo.

See also