224edo

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← 223edo224edo225edo →
Prime factorization 25 × 7
Step size 5.35714¢
Fifth 131\224 (701.786¢)
Semitones (A1:m2) 21:17 (112.5¢ : 91.07¢)
Consistency limit 15
Distinct consistency limit 15
Special properties

224 equal divisions of the octave (abbreviated 224edo or 224ed2), also called 224-tone equal temperament (224tet) or 224 equal temperament (224et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 224 equal parts of about 5.36 ¢ each. Each step represents a frequency ratio of 21/224, or the 224th root of 2.

Theory

224edo is a very strong 13-limit system, tempering out 32805/32768 in the 5-limit; 4375/4374, 16875/16807 and 65625/65536 in the 7-limit; 540/539, 1375/1372, 4000/3993 and notably, the quartisma in the 11-limit; and 625/624, 729/728, 1575/1573 and 2200/2197 in the 13-limit, leading to an abundance of precisely-tuned essentially tempered chords, including swetismic chords, squbemic chords, and petrmic chords in the 13-odd-limit, in addition to nicolic chords in the 15-odd-limit. It defines the optimal patent val for the octoid in the 7-, 11- and 13-limit, and for mirkwai, the 7-limit planar temperament tempering out 16875/16807. It also provides an excellent tuning for indra and shibi temperaments. It is the twelfth zeta integral edo.

224edo tempers the syntonic comma to 1/56th of the octave (4 steps) and as a corollary supports the barium temperament. As a consequence of this, the 224bb val (flattening the fifth by one step) is a tuning for meantone and is very close (0.15 cents) to the quarter-comma meantone fifth. The generator however reduces to 112edo, being 65\112.

Prime harmonics

Approximation of prime harmonics in 224edo
Harmonic 2 3 5 7 11 13 17 19 23 29 31
Error absolute (¢) +0.00 -0.17 -0.60 +0.82 +0.47 +0.54 +2.19 +2.49 -1.49 -1.01 +1.39
relative (%) +0 -3 -11 +15 +9 +10 +41 +46 -28 -19 +26
Steps
(reduced)
224
(0)
355
(131)
520
(72)
629
(181)
775
(103)
829
(157)
916
(20)
952
(56)
1013
(117)
1088
(192)
1110
(214)

Subsets and supersets

Since 224 = 32 × 7, 224edo has subset edos 2, 4, 8, 16, 32, 7, 14, 28, 56, and 112.

Regular temperament properties

Subgroup Comma List Mapping Optimal
8ve Stretch (¢)
Tuning Error
Absolute (¢) Relative (%)
2.3 [-355 224 [224 355]] +0.053 0.0534 1.00
2.3.5 32805/32768, [-5 -32 24 [224 355 520]] +0.122 0.1059 1.98
2.3.5.7 4375/4374, 16875/16807, 32805/32768 [224 355 520 629]] +0.018 0.2009 3.75
2.3.5.7.11 540/539, 1375/1372, 4000/3993, 32805/32768 [224 355 520 629 775]] -0.012 0.1899 3.54
2.3.5.7.11.13 540/539, 625/624, 729/728, 1375/1372, 2200/2197 [224 355 520 629 775 829]] -0.035 0.1805 3.37

Rank-2 temperaments

Table of rank-2 temperaments by generator
Periods
per 8ve
Generator* Cents* Associated
Ratio*
Temperaments
1 43\224 230.36 8/7 Gamera
1 59\224 316.07 6/5 Counterkleismic / counterlytic
1 65\224 348.21 11/9 Eris
1 71\224 380.36 56/45 Quanharuk
1 87\224 466.07 55/42 Hemiseptisix
1 93\224 498.21 4/3 Pontiac / ponta
1 103\224 551.79 11/8 Emkay
1 111\224 594.64 55/39 Gaster
2 93\224
(19\224)
498.21
(101.79)
4/3
(35/33)
Bipont
2 31\224 166.07 11/10 Pogo
2 33\224 176.79 195/176 Quatracot
2 39\224 208.93 44/39 Abigail
2 43\224 230.36 8/7 Hemigamera
4 71\224
(15\224)
380.36
(80.36)
81/65
(22/21)
Quasithird
4 93\224
(19\224)
498.21
(101.79)
4/3
(35/33)
Quadrant
7 97\224
(1\224)
519.64
(5.36)
27/20
(325/324)
Brahmagupta
7 93\224
(3\224)
498.21
(16.07)
4/3
(99/98)
Septant
8 93\224
(9\224)
498.21
(48.21)
4/3
(36/35)
Octant
8 109\224
(3\224)
583.93
(16.07)
7/5
(100/99)
Octoid
14 93\224
(3\224)
498.21
(16.07)
4/3
(105/104)
Silicon
28 93\224
(3\224)
498.21
(16.07)
4/3
(126/125)
Oquatonic
32 50\224
(1\224)
267.86
(5.36)
245/143
(???)
Germanium
32 93\224
(2\224)
498.21
(10.71)
4/3
(???)
Bezique
56 93\224
(3\224)
498.21
(16.07)
4/3
(126/125)
Barium

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

Music

Gene Ward Smith
Mercury Amalgam