Trivial temperament: Difference between revisions

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add note about name origin
Use common terms rather than unattested/rare idiosyncratic terms (including "Om temperament"!)
 
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A '''trivial temperament''' is something that fits the mathematical definition of "regular temperament", but is a unique, extreme case that people might be uncomfortable calling a "[[temperament]]". There are two kinds of trivial temperaments - [[JI]], in which nothing is tempered, and '''Om''' temperament, in which everything is tempered.
A '''trivial temperament''' is something that fits the mathematical definition of [[regular temperament]], but is a unique, extreme case that people might be uncomfortable calling a "[[temperament]]". There are two types of trivial temperaments: [[just intonation]], which leaves all intervals [[tempering|untempered]], and [[single-pitch tuning]], which [[tempering out|tempers out]] all intervals.


Just intonation is a codimension-0 "temperament", which means nothing is tempered. The set of commas that are tempered out is the set {1/1}, but that's still a set, so JI is still a regular temperament. There is an infinite family of these "temperaments", one for each subgroup of JI. The [[2-limit]] version is the equal temperament [[1edo]]. The [[3-limit]] version is the rank-2 temperament [[pythagorean]], which has all the properties of any other rank-2 temperament except that it tempers no commas. The [[5-limit]] version is rank-3, and so on. The mapping for this temperament is an nxn identity matrix, with wedgies of <1|, <<1||, <<<1|||... .
== Just intonation ==
{{Main| Just intonation }}


'''Om''' temperament is the rank-0 temperament, in which every interval is a comma. Thus all notes are represented by the same note. This is different from 1edo because not even octaves exist; it could be described as [[0edo]]. The mapping for this is the 0-val, <0 0 ... 0|.
The [[mapping]] for a [[just intonation subgroup]] of rank ''n'' is an ''n''×''n'' {{w|identity matrix}}, and transforms said subgroup to itself. In musical terms, this means that nothing is tempered. The set of commas that are tempered out is {1/1}, but that is still a valid set, so just intonation still counts as valid regular temperaments.  


The name "Om" is a reference to [[Wikipedia:Om|that syllable's use in Hindu meditation practices]]; [[Keenan Pepper]] gave it this name because there's only one temperament-distinct pitch in the whole system, in the same way that "Om" in the meditation sense is the only word you need to create the whole universe.  
There is an infinite family of these temperaments, one for each subgroup of JI. The 2-limit version is equivalent to [[1edo|1et]]. The [[3-limit]] version, or [[pythagorean tuning]], is a rank-2 temperament, which has all the properties of any other rank-2 temperament except that it tempers out no commas. 5-limit JI is rank-3, 7-limit JI is rank-4, etc.


[[Category:Temperament]]
[[User:VectorGraphics|Vector]] proposes the name ''identity temperament''{{idio}} for this family of temperaments.
[[Category:Theory]]
 
== Single-pitch tuning ==
{{Main| Single-pitch tuning }}
 
The single-pitch tuning is the rank-0 temperament, in which every interval is a comma. Thus all notes are represented by the same note. This is different from 1edo because not even octaves exist. The mapping for this is the 0-val, {{val| 0 0 … 0 }}, and its [[wedgie]] is a single entry.
 
As with JI, there is technically a temperament of a single pitch for every subgroup.
 
[[Gene Ward Smith]] proposes the name ''unison temperament'' for this family of temperaments<ref>http://www.robertinventor.com/tuning-math/s__12/msg_11050-11074.html</ref>, as all intervals are equated to the unison. [[Keenan Pepper]] proposes the name ''Om temperament''{{idio}}. [[Wikipedia:Om|''Om'']] is a reference to that syllable's use in Hindu meditation practices, for there is only one temperament-distinct pitch in the whole system, in the same way that ''Om'' in the meditation sense is the only word you need to create the whole universe.
 
== Notes and references ==
<references />
 
[[Category:Regular temperament theory]]

Latest revision as of 14:19, 6 October 2025

A trivial temperament is something that fits the mathematical definition of regular temperament, but is a unique, extreme case that people might be uncomfortable calling a "temperament". There are two types of trivial temperaments: just intonation, which leaves all intervals untempered, and single-pitch tuning, which tempers out all intervals.

Just intonation

The mapping for a just intonation subgroup of rank n is an n×n identity matrix, and transforms said subgroup to itself. In musical terms, this means that nothing is tempered. The set of commas that are tempered out is {1/1}, but that is still a valid set, so just intonation still counts as valid regular temperaments.

There is an infinite family of these temperaments, one for each subgroup of JI. The 2-limit version is equivalent to 1et. The 3-limit version, or pythagorean tuning, is a rank-2 temperament, which has all the properties of any other rank-2 temperament except that it tempers out no commas. 5-limit JI is rank-3, 7-limit JI is rank-4, etc.

Vector proposes the name identity temperament[idiosyncratic term] for this family of temperaments.

Single-pitch tuning

The single-pitch tuning is the rank-0 temperament, in which every interval is a comma. Thus all notes are represented by the same note. This is different from 1edo because not even octaves exist. The mapping for this is the 0-val, 0 0 … 0], and its wedgie is a single entry.

As with JI, there is technically a temperament of a single pitch for every subgroup.

Gene Ward Smith proposes the name unison temperament for this family of temperaments[1], as all intervals are equated to the unison. Keenan Pepper proposes the name Om temperament[idiosyncratic term]. Om is a reference to that syllable's use in Hindu meditation practices, for there is only one temperament-distinct pitch in the whole system, in the same way that Om in the meditation sense is the only word you need to create the whole universe.

Notes and references