325/324: Difference between revisions

Eufalesio (talk | contribs)
Made the equivalences easier to read
Ordinary analysis doesn't need list form
 
Line 4: Line 4:
| Comma = yes
| Comma = yes
}}
}}
The '''marveltwin comma''', '''325/324''', is a [[13-limit]] (also 2.3.5.13 [[subgroup]]) [[comma]] measuring about 5.3{{cent}}. Its significance is in that it marks the difference between:
The '''marveltwin comma''', '''325/324''', is a [[small comma|small]] [[13-limit]] (also 2.3.5.13 [[subgroup]]) [[superparticular ratio|superparticular]] [[comma]] measuring about 5.3 [[cent]]s. Its significance is in that it marks the difference between [[16/13]] and a stack of two [[10/9]]'s, and [[13/9]] and a stack of two [[6/5]]'s. It can also be expressed as the difference between [[1053/1024]] and a stack of two [[81/80]]'s.


* [[16/13]] and two [[10/9]]'s
In terms of other superparticular ratios, it is the difference between:
* [[13/8]] and [[81/50]] ([[8/5]] * [[81/80]])
* [[13/9]] and two [[6/5]]'s
* [[1053/1024]] and two [[81/80]]'s
* [[25/24]] and [[27/26]]
* [[25/24]] and [[27/26]]
* [[100/99]] and [[144/143]]
* [[100/99]] and [[144/143]]


Being a [[triangle-particular|triangle superparticular]], it factors neatly into ([[625/624]])([[676/675]]). Other factorizations are:   
Being a [[triangle-particular|triangle superparticular]], it factors neatly into ([[625/624]])([[676/675]]). Other factorizations are:   
* ([[385/384]])⋅([[2080/2079]])
* ([[364/363]])⋅([[3025/3024]])
* ([[352/351]])⋅([[4225/4224]])
* ([[351/350]])⋅([[4375/4374]])


* ([[385/384]])([[2080/2079]])
In the 17-limit it additionally factors into ([[595/594]])([[715/714]]).  
* ([[364/363]])([[3025/3024]])
* ([[352/351]])([[4225/4224]])
* ([[351/350]])([[4375/4374]])
* ([[595/594]])([[715/714]]) In the 17-limit.


== Temperaments ==
== Temperaments ==
Tempering out this comma leads to the rank-5 [[Marveltwin|marveltwin temperament]], which identifies [[16/13]] by two [[10/9]]'s stacked and enables [[marveltwin chords]]. The most significant further temperament is to temper out 625/624 and/or 676/675, equating 26/25 with 25/24~27/26. This in the 2.3.5.13 [[subgroup]] is the rank-2 [[cata]] temperament.  
[[Tempering out]] this comma leads to the rank-5 [[Marveltwin|marveltwin temperament]], which identifies [[16/13]] by two [[10/9]]'s stacked and enables [[marveltwin chords]]. The most significant further temperament is to temper out 625/624 and/or 676/675, equating 26/25 with 25/24~27/26. This in the 2.3.5.13 [[subgroup]] is the rank-2 [[cata]] temperament.  


== See also ==
== See also ==