# 18edt

 ← 17edt 18edt 19edt →
Prime factorization 2 × 32
Step size 105.664¢
Octave 11\18edt (1162.31¢)
Consistency limit 2
Distinct consistency limit 2

18edt is the division of the tritave into 18 equal parts of size 105.664 cents each. It has a decent 7 and an excellent 13, but a 5 which is 39 cents flat; if octaves were added and it was a sixth, it would count as a neutral sixth. The corresponding 5/3 is 845 cents, which is a neutral sixth between 8/5 and 5/3, which is really more of a 13/8, though this is allegedly a no-twos tuning. With octaves added, it also has a minor third and a major tenth which are both excellent as well as a minor thirteenth and major seventeenth which are still decent even though it skips actual octaves (in fact it is the non-octave semitone scale of 34edo). On the 3.7.13 subgroup it tempers out 351/343 and 2197/2187.

## Temperaments

As the double of 9edt, it is the analog of 14edo insofar if treating as it has a doubled harmonic chain. However, it, like 8edt, is not schismatic because 3:5:7 is a redundant chord. As a multiple of 9edt, it is the widest variety of 'White-Extraterrestrial-Tree' temperament.

18edt can also be used for the Electra temperament based on 15/11, although in this case its approximation to 13/11 is very sharp.

## Intervals

Step Cents Hekts Approximated interval Electra notation (J = 1/1)
0 1/1 J
1 105.664 72.222 16/15 J#, Kbb
2 211.328 144.444 9/8 Jx, Kb
3 316.993 216.667 6/5 K
4 422.657 288.889 9/7 K#, Lb
5 528.321 361.111 27/20 L
6 633.985 433.333 13/9 L#, Mbb
7 739.649 505.556 17/13 Lx, Mb
8 845.313 577.778 5/3 M
9 950.978 650 19/11 M#, Nbb
10 1056.642 722.222 9/5 Mx, Nb
11 1162.306 794.444 49/25 N
12 1267.97 866.667 27/13 N#, Ob
13 1373.634 938.889 20/9 O
14 1479.298 1011.111 7/3 O#, Pbb
15 1584.963 1083.333 5/2 Ox, Pb
16 1690.627 1155.556 8/3 P
17 1806.291 1227.778 45/16 P#, Jb
18 1901.955 1300 3/1 J