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← 7edf8edf9edf →
Prime factorization 23
Step size 87.7444¢ 
Octave 14\8edf (1228.42¢) (→7\4edf)
Twelfth 22\8edf (1930.38¢) (→11\4edf)
Consistency limit 2
Distinct consistency limit 2

8 equal divisions of the fifth (8edf, 8ed3/2) is the tuning system that divides the fifth into 8 steps of 87.7444 cents each, making it very nearly 88cET. It is related to the octacot temperament. 8edf corresponds to about 13.6761edo (similar to every third step of 41edo).


8edf can be notated either using native uranian (sesquitave) notation, where the notation repeats every period (i.e. just diatonic fifth), or using double sesquitave (Annapolis) notation, where the notation repeats every two periods (i.e. major diatonic ninth). This interprets 8edf as 16ed9/4, resulting in a tuning for the Natural and Harmonic Minor modes of Annapolis[6L 4s]. It can also be notated using tetratonic 4edf-based notation.

The naturals result from a semiwolf generator (~7/6). For sesquitave notation, letters A-E can be used. For double sesquitave notation, Greek numerals 1-10 can be used (Α,Β,Γ,Δ,Ε,Ϛ/Ϝ,Ζ,Η,Θ,Ι).

Scale Cents Approximate intervals Uranian Diatonic Notation
degree value 7-limit 11-limit 19-limit interval equivalent Uranian Annapolis Tetratonic notation
0 0 1 unison A Α C
1 87.7444 21/20 22/21 20/19, 19/18 min mos2nd minor second A# Α# ^C, vD
2 175.48875 10/9 21/19 maj mos2nd major second B Β D
3 263.2331 7/6 perf mos3rd subminor third C Γ ^D, vE
4 350.9775 60/49, 49/40 11/9 aug mos3rd neutral third C# Γ# E
5 438.7219 9/7 perf mos4th supermajor third D Δ ^E, vF
6 526.46625 27/20 19/14 min mos5th wolf fourth D# Δ# F
7 614.2106 10/7 27/19 maj mos5th augmented fourth E Ε ^F, vC
8 701.955 3/2 sesquitave just fifth A Ϛ/Ϝ C
9 789.6994 63/40 11/7 30/19 min mos7th minor sixth A# Ϛ#/Ϝ# ^C, vD
10 877.44375 5/3 63/38 maj mos7th major sixth B Ζ D
11 965.1881 7/4 perf mos8th subminor seventh C Η ^D, vE
12 1052.9325 90/49, 35/18 11/6 aug mos8th neutral seventh C# Η# E
13 1140.6769 27/14 perf mos9th supermajor seventh D Θ ^E, vF
14 1228.42125 81/40 57/28 min mos10th acute octave D# Θ# F
15 1316.1656 15/7 81/38 maj mos10th minor ninth E Ι ^F, vC
16 1403.91 9/4 double sesquitave major ninth A Α C

Scale workshop link for a keyboard/MIDI playable 8EDF (with graphical uranian scale, A=220Hz)

Rank 2 temperaments

MOS scales and temperament listed by generator size and period:


per octave

Generator Scale pattern Temperaments
1 1\8 1L5s, 1L6s (pathological)
1 3\8 3L2s (uranian) Semiwolf
2 3\8 2L 2s (augmented-like)


8EDF cheat sheet (sesquitave notation) - table only