Luna and hemithirds

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The 7-limit hemithirds temperament functions as a strong extension of didacus, the 2.5.7 subgroup temperament, in the range between 25edo and 31edo tuning, defined by tempering out 3136/3125 such that two of its generators (hemithird, ~28/25, around 193.2 cents) reach ~5/4, three reach ~7/5, and therefore five reach ~7/4. Hemithirds extends didacus by tempering out 1029/1024, such that three intervals of ~8/7 reach 3/2, therefore finding 4/3 after fifteen generators in total.

Luna is a restriction of hemithirds to the 5-limit that is a microtemperament, supported by such high-precision tuning systems as 118edo and 441edo; another notable tuning of luna is 1000edo. It can further be re-extended to the 7-limit in the form of lunatic, but that extension is extremely complex (finding the 7th harmonic at 113 generators down).

See Hemimean clan #Hemithirds and Luna family #Luna for more information.

Intervals

See Didacus#Interval chain.

Chords

Tuning spectrum

Gencom: [2 28/25; 196/195 352/351 385/384 625/624]

Gencom mapping: [1 4 2 2 7 0], 0 -15 2 5 -22 23]]

Eigenmonzo
(Unchanged-interval)
Generator
(¢)
Comments
14/13 192.872
12/11 192.948
15/11 192.995
13/10 193.058
16/13 193.066
13/11 193.094
15/13 193.118
13/12 193.120
11/8 193.122
11/10 193.125
18/13 193.144
5/4 193.157
6/5 193.198 5-odd-limit minimax
10/9 193.200
4/3 193.203
16/15 193.210
14/11 193.241 11-odd-limit minimax
9/7 193.283 9-odd-limit minimax
7/6 193.344 7-odd-limit minimax
15/14 193.364
11/9 193.426
8/7 193.765
7/5 194.171