# 1001edo

← 1000edo | 1001edo | 1002edo → |

**1001 equal divisions of the octave** (abbreviated **1001edo** or **1001ed2**), also called **1001-tone equal temperament** (**1001tet**) or **1001 equal temperament** (**1001et**) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 1001 equal parts of about 1.2 ¢ each. Each step represents a frequency ratio of 2^{1/1001}, or the 1001st root of 2.

1001edo is inconsistent to the 5-odd-limit and harmonic 3 is about halfway between its steps. Otherwise, it has good approximations to harmonics 7, 9, 11, 13, 19, and 23, making it suitable for a 2.9.7.11.13.19.23 subgroup interpretation, with an optional addition of either 5, or 15. In such a subgroup, it tempers out 14651/14641, 157757/157696, and 184877/184832.

Taking the full 23-limit enables to determine that 1001edo tempers out 1288/1287, 2300/2299, 2737/2736, 2926/2925, and 5776/5775. Using the 1001b val, that is putting the 3/2 fifth on the 585th step instead of the 586th, 1001edo tempers out 936/935, 1197/1196, and 1521/1520, as well as the parakleisma.

### Odd harmonics

Harmonic | 3 | 5 | 7 | 9 | 11 | 13 | 15 | 17 | 19 | 21 | 23 | |
---|---|---|---|---|---|---|---|---|---|---|---|---|

Error | Absolute (¢) | +0.543 | -0.300 | -0.195 | -0.114 | +0.131 | -0.168 | +0.243 | +0.539 | -0.210 | +0.348 | -0.103 |

Relative (%) | +45.3 | -25.0 | -16.2 | -9.5 | +10.9 | -14.0 | +20.3 | +45.0 | -17.5 | +29.0 | -8.6 | |

Steps (reduced) |
1587 (586) |
2324 (322) |
2810 (808) |
3173 (170) |
3463 (460) |
3704 (701) |
3911 (908) |
4092 (88) |
4252 (248) |
4397 (393) |
4528 (524) |

### Subsets and supersets

Since 1001 factorizes as 7 × 11 × 13, 1001edo has subset edos 7, 11, 13, 77, 91, and 143.