Trivial temperament: Difference between revisions

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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, &lt;0 0 ... 0|. It could also be called the '''unison temperament'''<ref>http://www.robertinventor.com/tuning-math/s__12/msg_11050-11074.html</ref>, following the common pattern whereby temperaments are named after the intervals they [[temper out]], where in this case the interval tempered out is the [[unison]] (and therefore all intervals are brought together in unison). 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.  
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.
 
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.
 
[[User:VectorGraphics|Vector]] proposes the name ''identity temperament''{{idio}} for this family of temperaments.
 
== 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]]
[[Category:Regular temperament theory]]
[[Category: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