5edf

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← 4edf 5edf 6edf →
Prime factorization 5 (prime)
Step size 140.391 ¢ 
Octave 9\5edf (1263.52 ¢)
Twelfth 14\5edf (1965.47 ¢)
Consistency limit 2
Distinct consistency limit 2

5 equal divisions of the perfect fifth (abbreviated 5edf or 5ed3/2) is a nonoctave tuning system that divides the interval of 3/2 into 5 equal parts of about 140 ¢ each. Each step represents a frequency ratio of (3/2)1/5, or the 5th root of 3/2. It corresponds to 8.5476 edo.

Theory

5edf is close to the bleu generator chain and every second step of 17edo. 4 steps of 5edf is a fraction of a cent away to the seventh harmonic (which is 112/81 instead of 7/4 since the equave is 3/2), which is an extremely accurate approximation for the size of this scale.

Harmonics

Approximation of harmonics in 5edf
Harmonic 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Error Absolute (¢) +63.5 +63.5 -13.4 +21.5 -13.4 +0.6 +50.2 -13.4 -55.4 +60.4 +50.2 +52.0 +64.1 -55.4 -26.7
Relative (%) +45.2 +45.2 -9.5 +15.3 -9.5 +0.4 +35.7 -9.5 -39.4 +43.0 +35.7 +37.0 +45.6 -39.4 -19.0
Steps
(reduced)
9
(4)
14
(4)
17
(2)
20
(0)
22
(2)
24
(4)
26
(1)
27
(2)
28
(3)
30
(0)
31
(1)
32
(2)
33
(3)
33
(3)
34
(4)

Subsets and supersets

5edf is the 3rd prime edf, after 3edf and before 7edf.

Intervals

# Cents Approximate ratios Neptunian notation
0 0.0 1/1 perfect unison C
1 140 13/12, 49/45 augmented unison, minor second C#, Db
2 281 13/11, 20/17, 75/64 major second, minor third D, Eb
3 421 14/11, 23/18 major third, diminished fourth E, Fb
4 562 11/8, 18/13, 25/18 perfect fourth F
5 702 3/2 perfect fifth C
6 842 13/8, 18/11, 21/13 augmented fifth, minor sixth C#, Db
7 983 7/4, 30/17 major sixth, minor seventh D, Eb
8 1123 major seventh, minor octave E, Fb
9 1264 major octave F
10 1404 9/4 C