442/441
Interval information |
Sothoruru comma
reduced
(Shannon, [math]\sqrt{nd}[/math])
442/441, the seminaiadma, is a small 17-limit superparticular comma about 3.9 cents in size. It is the difference between 21/17 and 26/21, and forms the amount by which a stack consisting of 13/8 and 17/16 exceeds a stack of two 21/16s. It differs from 441/440 (werckisma) by 194481/194480 (scintillisma) – an unnoticeable comma measuring ~0.0089 cents. By tempering it out is defined the seminaiadmic temperament, which enables the seminaiadmic chords.
Commatic relations
This comma identifies itself as the difference between the following superparticular pairs:
- 85/84 and 105/104
- 136/135 and 196/195
- 169/168 and 273/272
- 221/220 and 441/440
- 289/288 and 833/832
- 325/324 and 1225/1224
- 351/350 and 1701/1700
- 364/363 and 2058/2057
- 441/440 and 194481/194480
It factors into the following superparticular pairs:
- 540/539 and 2431/2430
- 561/560 and 2080/2079
- 595/594 and 1716/1715
- 676/675 and 1275/1274
- 715/714 and 1156/1155
Etymology
The name seminaiadma was named by Xenllium in 2023, for the following reasons - its size is about a half of minor naiadma, 221/220 (similar to semicomma, whose size is about a half of syntonic comma). Tempering it out leads equating 21/17 and 26/21 into a single submajor third interval, two of which give an interseptimal interval, 26/17 (octave complement of a naiadic interval, 17/13).