Tuning map: Difference between revisions

Cmloegcmluin (talk | contribs)
prefer basis element to formal prime
Cmloegcmluin (talk | contribs)
m depluralize for clarity & consistency
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It may be helpful, then, to think of the units of each entry of a tuning map as c/p (read "cents per prime"), oct/p (read "octaves per prime"), or any other logarithmic pitch unit per prime.
It may be helpful, then, to think of the units of each entry of a tuning map as c/p (read "cents per prime"), oct/p (read "octaves per prime"), or any other logarithmic pitch unit per prime.


== Generators tuning map ==
== Generator tuning map ==


A '''generators tuning map''' is like a (temperament) tuning map, but each entry gives the size in cents or octaves of a different [[generator]], rather than of a formal prime.  
A '''generator tuning map''' is like a (temperament) tuning map, but each entry gives the size in cents or octaves of a different [[generator]], rather than of a formal prime.  


It may be helpful, then, to think of the units of each entry of a generators tuning map as c/g (read "cents per generator"), oct/g (read "octaves per generator"), or any other logarithmic pitch unit per generator.
It may be helpful, then, to think of the units of each entry of a generator tuning map as c/g (read "cents per generator"), oct/g (read "octaves per generator"), or any other logarithmic pitch unit per generator.


From the generators tuning map <math>𝒈</math> and the mapping <math>M</math>, we can obtain the tuning map <math>𝒕</math> as <math>𝒈.M</math>.
From the generator tuning map <math>𝒈</math> and the mapping <math>M</math>, we can obtain the tuning map <math>𝒕</math> as <math>𝒈.M</math>.


== Example ==
== Example ==
Consider meantone temperament, with the mapping {{ket|{{map| 1 1 0 }} {{map| 0 1 4 }} }}. Temperaments, as represented by mappings, remain abstract; while this mapping does convey that the generators are ~2/1 and ~3/2, it does not specify exact tunings for those approximations. One example tuning would be quarter-comma meantone, where the octave is pure and the perfect fifth is 5<sup>1/4</sup>; this gives a generators tuning map of {{map| 1200.000 696.578 }}.  
Consider meantone temperament, with the mapping {{ket|{{map| 1 1 0 }} {{map| 0 1 4 }} }}. Temperaments, as represented by mappings, remain abstract; while this mapping does convey that the generators are ~2/1 and ~3/2, it does not specify exact tunings for those approximations. One example tuning would be quarter-comma meantone, where the octave is pure and the perfect fifth is 5<sup>1/4</sup>; this gives a generator tuning map of {{map| 1200.000 696.578 }}.  


The tuning map from <math>𝒈</math> = {{map| 1200.000 696.578 }} and <math>M</math> = {{ket|{{map| 1 1 0 }} {{map| 0 1 4 }} }} is <math>𝒕</math> = {{map| 1200.000 1896.578 2786.314 }}.  
The tuning map from <math>𝒈</math> = {{map| 1200.000 696.578 }} and <math>M</math> = {{ket|{{map| 1 1 0 }} {{map| 0 1 4 }} }} is <math>𝒕</math> = {{map| 1200.000 1896.578 2786.314 }}.  
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== With respect to the JIP ==
== With respect to the JIP ==
[[JI]] can be conceptualized as the temperament where nothing is [[tempered out]], and as such, the untempered primes can be thought of as its generators, or of course its basis elements. So, JI subgroups have generators tuning maps and tuning maps too; the generators tuning maps and tuning maps are always the same thing as each other, and they are all subsets of the entries of the [[JIP]].
[[JI]] can be conceptualized as the temperament where nothing is [[tempered out]], and as such, the untempered primes can be thought of as its generators, or of course its basis elements. So, JI subgroups have generator tuning maps and tuning maps too; the generator tuning maps and tuning maps are always the same thing as each other, and they are all subsets of the entries of the [[JIP]].


== With respect to linear algebra ==
== With respect to linear algebra ==
A tuning map can be thought of either as a one-row matrix or as a covector. The same is true of generators tuning maps.
A tuning map can be thought of either as a one-row matrix or as a covector. The same is true of generator tuning maps.


[[Category:Tuning]]
[[Category:Tuning]]