Copper comma

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Interval information
Factorization 2-481 × 3261 × 529
Monzo [-481 261 29
Size in cents 13.352928¢
Name copper comma
Color name L41y29-33, fowela-theneyo negative 33rd
FJS name [math]-[/math]
Special properties reduced,
reduced harmonic
Tenney height (log2 nd) 962.011
Weil height (log2 max(n, d)) 962.022
Wilson height (sopfr (nd)) 1890
Harmonic entropy
(Shannon, [math]\sqrt{n\cdot d}[/math])
~3.07811 bits
Comma size small
open this interval in xen-calc

Copper comma, or alternately 29-atom is a 5-limit comma which is to 29edo as is the Kirnberger's atom is to 12edo.


Tempering it out results in the rank-2 copper temperament, which splits the octave into 29 parts, and the reduced generator is the difference between a more precise fifth and the 29-tone-tempered one, just as atomic does to 12edo. See: 29th-octave temperaments#Copper.

A circle of 29 of the sharpened fifths equal to 98415/65536 (monzo: [-16 9 1), differs from 17 octaves by the copper comma. The difference is that since 29edo is an above-pythagorean temperament, the copper fifth is sharp of 3/2. Notably, in the case of copper, the comma which sharpens the fifth to be close to 29edo's is still the schisma, 32805/32768.