Würschmidt comma
(Redirected from Wuerschmidt comma)
Ratio | 393216/390625 |
Monzo | [17 1 -8⟩ |
Size in cents | 11.445 |
Name(s) | Würschmidt comma |
The Würschmidt comma, 393216/390625 = [17 1 -8⟩, is a 5-limit comma of 11.4 cents.
It is the amount by which eight major thirds fall short of a perfect fifth, octave-reduced: ((5/4)^{8} × 393216/390625) / 4 = 3/2.
Therefore, it is also the amount by which seven major thirds fall short of 24/5 (i.e. 6/5 plus two octaves). In other words, ((5/4)^{7} × 393216/390625) / 4 = 6/5.
Tempering it out leads to würschmidt temperament. As in meantone, it implies that 3/2 will be tempered flat and/or 5/4 will be tempered sharp, and therefore 6/5 will be tempered flat.