Pythagorean comma: Difference between revisions

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The '''Pythagorean''' or '''ditonic comma''' is the interval with the ratio '''531441/524288''' (= {{Monzo| -19 12 }}). It could also be called the 12-comma as it is the amount by which twelve fifths exceed seven octaves, or in other words (3/2)<sup>12</sup>/2<sup>7</sup> and it also can be written as the ratio between the apotome and the Pythagorean minor second, ([[2187/2048]])/([[256/243]]).  
The '''Pythagorean''' or '''ditonic comma''' is the interval with the ratio '''531441/524288''' (= {{Monzo| -19 12 }}). It could also be called the 12-comma as it is the amount by which twelve fifths exceed seven octaves, or in other words (3/2)<sup>12</sup>/2<sup>7</sup> and it also can be written as the ratio between the apotome and the Pythagorean minor second, ([[2187/2048]])/([[256/243]]). In addition, it also equates six [[9/8]] major seconds with an octave.  


== Temperament ==
== Temperament ==

Revision as of 13:00, 8 May 2022

Interval information
Ratio 531441/524288
Factorization 2-19 × 312
Monzo [-19 12
Size in cents 23.46001¢
Names Pythagorean comma,
ditonic comma
Color name LLw-2, Lalawa comma
FJS name [math]\displaystyle{ \text{d}{-2} }[/math]
Special properties reduced,
reduced harmonic
Tenney norm (log2 nd) 38.0196
Weil norm (log2 max(n, d)) 38.0391
Wilson norm (sopfr(nd)) 74
Open this interval in xen-calc

The Pythagorean or ditonic comma is the interval with the ratio 531441/524288 (= [-19 12). It could also be called the 12-comma as it is the amount by which twelve fifths exceed seven octaves, or in other words (3/2)12/27 and it also can be written as the ratio between the apotome and the Pythagorean minor second, (2187/2048)/(256/243). In addition, it also equates six 9/8 major seconds with an octave.

Temperament

Tempering out this comma leads to the Pythagorean family of temperaments. For EDOs up to 300, it is tempered out if and only if the EDO is a multiple of 12, and hence for instance by 12edo, 24edo, 72edo and 84edo.

See also