Holdrian comma: Difference between revisions
mNo edit summary |
m Rewrite the ratio; +category; -see also that's already incorporated in the body text |
||
| Line 1: | Line 1: | ||
{{Infobox Interval | {{Infobox Interval | ||
| Ratio = | | Ratio = 2^{1/53} | ||
| Cents = 22.6415 | | Cents = 22.6415 | ||
| Name = Holdrian comma, Holder’s comma, Arabian comma, 1 step of 53edo | | Name = Holdrian comma, Holder’s comma, Arabian comma, 1 step of 53edo | ||
| Line 21: | Line 21: | ||
Holder 1731 writes that [[Marin Mersenne]] had calculated 58<sup>1</sup>/<sub>4</sub>s in the octave; Mercator "working by the logarithms, finds out but 55, and a little more."<ref name=Holder-1731/> | Holder 1731 writes that [[Marin Mersenne]] had calculated 58<sup>1</sup>/<sub>4</sub>s in the octave; Mercator "working by the logarithms, finds out but 55, and a little more."<ref name=Holder-1731/> | ||
One of these intervals was first described by [[Jing Fang]] in 45 BCE.<ref name=Touma/> Mercator applied logarithms to determine that <math>\ \sqrt[55]{2\;}\ </math> (≈ 21.8182 cents) was nearly equivalent to a syntonic comma of ≈ 21.5063 cents (a feature of the [[historical temperaments|prevalent]] [[meantone]] temperament | One of these intervals was first described by [[Jing Fang]] in 45 BCE.<ref name=Touma/> Mercator applied logarithms to determine that <math>\ \sqrt[55]{2\;}\ </math> (≈ 21.8182 cents) was nearly equivalent to a syntonic comma of ≈ 21.5063 cents (a feature of the [[historical temperaments|prevalent]] [[meantone]] temperament of the time). He also considered that an "artificial comma" of <math>\ \sqrt[53]{2\;}\ </math> might be useful, because 31 octaves could be practically approximated by a cycle of 53 [[just fifth]]s. | ||
William Holder, for whom the ''Holdrian'' comma is named, favored this latter unit because the intervals of [[53edo]] are closer to [[just intonation]] than to [[55edo]]. Thus Mercator's comma and the Holdrian comma are two distinct but nearly equal intervals. | William Holder, for whom the ''Holdrian'' comma is named, favored this latter unit because the intervals of [[53edo]] are closer to [[just intonation]] than to [[55edo]]. Thus Mercator's comma and the Holdrian comma are two distinct but nearly equal intervals. | ||
| Line 30: | Line 30: | ||
== See also == | == See also == | ||
* [[Mercator's comma]] | * [[Mercator's comma]] | ||
* [[Historical temperaments]] | * [[Historical temperaments]] | ||
== Notes == | == Notes == | ||
[[Category:53edo]] | |||
[[Category:Small commas]] | [[Category:Small commas]] | ||
[[Category:Commas named after individuals]] | [[Category:Commas named after individuals]] | ||