Negri comma: Difference between revisions
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'''16875/16384''' is the 51.120 [[cent]] interval called the '''negri comma''' or double augmentation diesis. It is the amount by which four classical major thirds exceed three fourths, that is, ([[5/4]])<sup>4</sup>/([[4/3]])<sup>3</sup>, and is also the amount by which three [[16/15|diatonic semitones (16/15)]] fall short of a classical major third, that is, (5/4)/(16/15)<sup>3</sup>. Another characterization of this comma is the difference between the [[256/243|Pythagorean limma (256/243)]] and a stack of two [[25/24|classical chromas (25/24)]]. | '''16875/16384''' is the 51.120 [[cent]] interval called the '''negri comma''' or double augmentation diesis. It is the amount by which four classical major thirds exceed three fourths, that is, ([[5/4]])<sup>4</sup>/([[4/3]])<sup>3</sup>, and is also the amount by which three [[16/15|diatonic semitones (16/15)]] fall short of a classical major third, that is, (5/4)/(16/15)<sup>3</sup>. Another characterization of this comma is the difference between the [[256/243|Pythagorean limma (256/243)]] and a stack of two [[25/24|classical chromas (25/24)]]. | ||
It factors into simpler commas as ([[81/80]])([[3125/3072]]), the syntonic comma and the magic comma. Tempering it out leads to [[5-limit]] [[negri]] temperament, which is closely associated with [[19edo]]. | It factors into simpler commas as ([[81/80]])⋅([[3125/3072]]), the syntonic comma and the magic comma. In the [[7-limit]], it factors into ([[225/224]])⋅([[525/512]]), (225/224)<sup>2</sup>⋅([[49/48]]), or (225/224)<sup>3</sup>⋅([[686/675]]). | ||
== Temperaments == | |||
Tempering it out leads to [[5-limit]] [[negri]] temperament, which is closely associated with [[19edo]]. | |||
== Etymology == | == Etymology == | ||