User:Zhenlige/Logical tempering: Difference between revisions
Created page with "'''Logical tempering''' means using a regular temperament as a category system. For example, diatonic interval degrees are the result of logical tempering 3-limit into 7et, and chromatic degrees are the result of 12et." Tags: Mobile edit Mobile web edit |
No edit summary |
||
| (7 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
'''Logical tempering''' means using a [[regular temperament]] | {{../en2zh}} | ||
'''Logical tempering'''{{idio}} means using a [[regular temperament]] (called the '''logical temperament'''{{idio}}) to get “abstract” notes and intervals, but not directly the actual played notes. Different from “real” tempering, a logical temperament with [[torsion]] is allowed. The commas tempered out in the logical temperament are sometimes called “chromas”, which is a generalization of the concept of MOS [[chroma]]s. | |||
Multiple logical temperaments can be used at the same time. For example, one may first categorize intervals as alterations of [[3-limit]] intervals, and then logically temper out [[2187/2048]] to get [[5L 2s|diatonic]] degrees. Alternatively, one may use the 5-, 7- and 12-form degree systems in the same piece. | |||
When the actual notes are already tempered, to get unambiguous results, the logical temperament should be based on the tempered notes i.e. it should [[support]] the actual temperament. | |||
== Examples == | |||
[[Octave equivalence]] can be thought as logically tempering out [[2/1]]. | |||
The [[5L 2s|diatonic]] degrees (seconds, thirds etc.) of [[3-limit]] intervals are the result of logical tempering into [[7edo|7et]], tempering out the diatonic [[chroma]] [[2187/2048]]. Similarly, every [[MOS]]-based degree system can be thought as a logical temperament based on the equalized scale. | |||
The conventional categorization of [[7-limit]] intervals treats [[5/4]] as a major third and [[7/4]] as a minor seventh, which implies [[dominant (temperament)|dominant]] as the logical temperament. A piece using [[adaptive JI]] with that framework can be thought as a dynamic [[detempering]] of a piece in dominant. Alternatively, 7/4 can be considered as an augmented sixth, giving [[septimal meantone]] logic. | |||
The classical triads are made by stacking [[5/4]] and [[6/5]] intervals, meaning their difference [[25/24]] is a chroma, giving a [[dicot]] framework. Merging it with an actual [[5-limit]] [[rank]]-2 temperament gives a unique MOS structure. For example, [[meantone]] gives the famous [[5L 2s]] diatonic scale, and [[diaschismic]] gives [[2L 8s]]. | |||