UD
A UD, or utonal division, is a kind of arithmetic and monotonic tuning.
A UD is a specific (rational) type of ELD.
undertone mode, or under-n scale (equivalent to n-UDO)
n-UDp: n utonal divisions of interval p
An n-EDL is equivalent to a 2n-UDO (therefore EDL cannot be used to represent a UDO with an odd value for n).
| quantity | (0) | 1 | 2 | 3 | 4 |
|---|---|---|---|---|---|
| frequency (f) | (8/8) | 8/7 | 8/6 | 8/5 | 8/4 |
| pitch (log₂f) | (0) | 0.19 | 0.42 | 0.68 | 1.00 |
| length (1/f) | (1/1) | 7/8 | 3/4 | 5/8 | 1/2 |