888edo
← 887edo | 888edo | 889edo → |
888 equal divisions of the octave (abbreviated 888edo or 888ed2), also called 888-tone equal temperament (888tet) or 888 equal temperament (888et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 888 equal parts of about 1.35 ¢ each. Each step represents a frequency ratio of 21/888, or the 888th root of 2.
888edo is inconsistent to the 5-odd-limit and harmonic 3 is about halfway between its steps. Otherwise it is excellent in approximating harmonics 5, 7, 9, 11, and 13, making it suitable for a 2.9.5.7.11.13 subgroup interpretation. The equal temperament tempers out 4096/4095, 6656/6655, 9801/9800, 10648/10647, 105644/105625, 151263/151200, and 250047/250000 in the above subgroup.
Odd harmonics
Harmonic | 3 | 5 | 7 | 9 | 11 | 13 | 15 | 17 | 19 | 21 | 23 | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Error | Absolute (¢) | -0.604 | +0.173 | +0.093 | +0.144 | +0.033 | +0.013 | -0.431 | +0.450 | -0.216 | -0.511 | +0.104 |
Relative (%) | -44.7 | +12.8 | +6.9 | +10.7 | +2.5 | +1.0 | -31.9 | +33.3 | -16.0 | -37.8 | +7.7 | |
Steps (reduced) |
1407 (519) |
2062 (286) |
2493 (717) |
2815 (151) |
3072 (408) |
3286 (622) |
3469 (805) |
3630 (78) |
3772 (220) |
3900 (348) |
4017 (465) |
Subsets and supersets
Since 888 factors into 23 × 3 × 37, 888edo has subset edos 2, 3, 4, 6, 8, 12, 24, 37, 74, 111, 148, 222, 296, and 444. 1776edo, which doubles it, provides a good correction for harmonic 3.