A brief introduction to Regular Temperament Theory: Difference between revisions
Dave Keenan (talk | contribs) Removed ref to geometric algebra. Included ref to multilinear algebra. |
Dave Keenan (talk | contribs) Removed references to exterior algebra and wedgies now that canonical mappings are available. |
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These two extremes were well explored prior to RTT. What RTT did was open up a vast middle ground between JI and ET, where the number of generators is greater than one but less than the number of primes being approximated. These are called regular temperaments (RT). Only a very small region of that middle ground had been explored prior to RTT, namely the "[[meantone]]" region that approximates primes 2, 3 and 5, using two generators which are an octave (prime 2) and a slightly narrow fifth (approximate 2:3). | These two extremes were well explored prior to RTT. What RTT did was open up a vast middle ground between JI and ET, where the number of generators is greater than one but less than the number of primes being approximated. These are called regular temperaments (RT). Only a very small region of that middle ground had been explored prior to RTT, namely the "[[meantone]]" region that approximates primes 2, 3 and 5, using two generators which are an octave (prime 2) and a slightly narrow fifth (approximate 2:3). | ||
When the generation of tunings is formulated in this way, the tools of linear algebra can be applied. | When the generation of tunings is formulated in this way, the tools of linear algebra can be applied. | ||
The defining thing about a regular temperament is the the count of each generator required to approximate each prime number.<ref>Strictly speaking, it is the [[ | The defining thing about a regular temperament is the the count of each generator required to approximate each prime number.<ref>Strictly speaking, it is the [[Canonical_form|canonical form]] of the rows of the mapping matrix that defines the temperament, because you can replace any set of generators with linear combinations of those generators, and change the mapping accordingly, to obtain the same temperament.</ref> This is called the temperament's [[Temperament_Mapping_Matrices_(M-maps)|mapping]], and can be represented as a matrix. | ||
We can then institute computer searches to find optimum mappings, with our desired balance of error versus complexity. Many such searches have been done and [[Tour_of_Regular_Temperaments|many resulting temperaments named and catalogued]]. | We can then institute computer searches to find optimum mappings, with our desired balance of error versus complexity. Many such searches have been done and [[Tour_of_Regular_Temperaments|many resulting temperaments named and catalogued]]. | ||
<references/> | <references/> | ||