470edo

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← 469edo470edo471edo →
Prime factorization 2 × 5 × 47
Step size 2.55319¢
Fifth 275\470 (702.128¢) (→55\94)
Semitones (A1:m2) 45:35 (114.9¢ : 89.36¢)
Consistency limit 5
Distinct consistency limit 5

470 equal divisions of the octave (abbreviated 470edo or 470ed2), also called 470-tone equal temperament (470tet) or 470 equal temperament (470et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 470 equal parts of about 2.553 ¢ each. Each step represents a frequency ratio of 21/470, or the 470th root of 2.

Theory

470 = 5 × 94, and 470edo shares the fifth with 94edo. Unlike 94edo, however, 470edo is only consistent to the 5-odd-limit. Using the patent val, the equal temperament tempers out 703125/702464, 823543/820125, and 1500625/1492992 in the 7-limit; 3025/3024, 4000/3993, 6250/6237, 19712/19683, and 117649/117128 in the 11-limit. It supports uniwiz and decimetra.

Prime harmonics

Approximation of prime harmonics in 470edo
Harmonic 2 3 5 7 11 13 17 19 23 29 31
Error absolute (¢) +0.00 +0.17 -0.78 -1.17 +0.17 -0.53 -0.27 +1.21 -0.19 -0.64 -1.21
relative (%) +0 +7 -31 -46 +7 -21 -11 +47 -7 -25 -47
Steps
(reduced)
470
(0)
745
(275)
1091
(151)
1319
(379)
1626
(216)
1739
(329)
1921
(41)
1997
(117)
2126
(246)
2283
(403)
2328
(448)

Subsets and supersets

Since 470 factors into 2 × 5 × 47, 470edo has subset edos 2, 5, 10, 47, 94, and 235.

Regular temperament properties

Subgroup Comma List Mapping Optimal
8ve Stretch (¢)
Tuning Error
Absolute (¢) Relative (%)
2.3.5 1600000/1594323, [-77 -10 40 [470 745 1091]] +0.0759 0.1897 7.43
2.3.5.7 703125/702464, 1500625/1492992, 1600000/1594323 [470 745 1091 1319]] +0.1608 0.2205 8.64
2.3.5.7.11 3025/3024, 4000/3993, 19712/19683, 117649/117128 [470 745 1091 1319 1626]] +0.1187 0.2144 8.40
2.3.5.7.11.13 625/624, 1575/1573, 2080/2079, 13720/13689, 15379/15360 [470 745 1091 1319 1626 1739]] +0.1227 0.1959 7.67
2.3.5.7.11.13.17 595/594, 625/624, 833/832, 1575/1573, 3185/3179, 8624/8619 [470 745 1091 1319 1626 1739 1921]] +0.1148 0.1824 7.14

Rank-2 temperaments

Table of rank-2 temperaments by generator
Periods
per 8ve
Generator* Cents* Associated
Ratio*
Temperaments
1 133\470 339.57 243/200 Amity (5-limit)

* octave-reduced form, reduced to the first half-octave, and minimal form in parentheses if it is distinct