2197/2187: Difference between revisions

From Xenharmonic Wiki
Jump to navigation Jump to search
Wikispaces>FREEZE
No edit summary
BudjarnLambeth (talk | contribs)
mNo edit summary
 
(13 intermediate revisions by 8 users not shown)
Line 1: Line 1:
Threedie, the interval 13^3/3^7, is a 3.13 analog of the 2.5 [[128/125|diesis]], 2^7/5^3. Tempering by it, instead of chopping the octave into three sharp 5/4s, chops the tritave (3) into three slightly flat 13/9s, since (13/9)^3/3 = 2197/2187. 596 provides the optimal patent val for the corresponding rank five temperament.
{{Infobox Interval
| Name = threedie
| Color name = s3o<sup>3</sup>2, satritho 2nd,<br>Satritho comma
| Comma = yes
}}
 
The '''threedie''', '''2197/2187''', is a 3.13-[[subgroup]] analog of the 2.5-subgroup [[128/125|diesis]]. Measuring about 7.9{{cent}}, it is a [[small comma]]. Analogous to [[tempering out]] the diesis, which divides the octave into three sharp [[5/4]]'s, tempering out the threedie divides the [[tritave]] into three slightly flat [[13/9]]'s, since (13/9)<sup>3</sup>/3 = 2197/2187. Furthermore, tempering out the threedie divides [[9/8]] into three instances of [[27/26]]. [[596edo]] provides the optimal patent val for the corresponding rank-5 temperament.
 
It factors into simpler commas in the 2.3.5.13 subgroup as ([[325/324]])([[676/675]]), or can be expressed in the 2.3.7.13 subgroup as ([[169/168]])/([[729/728]]), i.e. S13/S27.
 
[[Category:Commas with unknown etymology]]

Latest revision as of 23:57, 15 November 2024

Interval information
Ratio 2197/2187
Factorization 3-7 × 133
Monzo [0 -7 0 0 0 3
Size in cents 7.897979¢
Name threedie
Color name s3o32, satritho 2nd,
Satritho comma
FJS name [math]\displaystyle{ \text{dd2}^{13,13,13} }[/math]
Special properties reduced
Tenney height (log2 nd) 22.1961
Weil height (log2 max(n, d)) 22.2026
Wilson height (sopfr(nd)) 60
Comma size small
S-expression S25 * S262
Open this interval in xen-calc

The threedie, 2197/2187, is a 3.13-subgroup analog of the 2.5-subgroup diesis. Measuring about 7.9 ¢, it is a small comma. Analogous to tempering out the diesis, which divides the octave into three sharp 5/4's, tempering out the threedie divides the tritave into three slightly flat 13/9's, since (13/9)3/3 = 2197/2187. Furthermore, tempering out the threedie divides 9/8 into three instances of 27/26. 596edo provides the optimal patent val for the corresponding rank-5 temperament.

It factors into simpler commas in the 2.3.5.13 subgroup as (325/324)(676/675), or can be expressed in the 2.3.7.13 subgroup as (169/168)/(729/728), i.e. S13/S27.