161edo: Difference between revisions
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{{Infobox ET}} | {{Infobox ET}} | ||
{{ | {{ED intro}} | ||
== Theory == | == Theory == | ||
161et [[tempering out|tempers out]] the [[würschmidt comma]], 393216/390625, in the [[5-limit]]; [[3136/3125]], [[6144/6125]] and [[2401/2400]] in the [[7-limit]]; [[243/242]], [[441/440]], [[540/539]] and [[5632/5625]] in the [[11-limit]]; and [[351/350]], [[847/845]], [[1001/1000]], [[1188/1183]], [[1575/1573]] and [[1716/1715]] in the [[13-limit]]. It serves as the [[optimal patent val]] for the [[mintone]] temperament in the 5-, 7-, 11- and 13-limit. | 161edo has a [[perfect fifth]] slightly sharp of that of [[12edo]], such that it maps the [[Pythagorean comma]] to one step. It approximates many of the low primes fairly well; however, it is only consistent to the [[7-odd-limit]], due to [[10/9]] being mapped too sharply from prime [[5/1|5]] being sharp, while [[3/1|3]] is flat. Nonetheless it does well for its size in higher limits, with the inconsistent intervals in the [[23-odd-limit]] being 9/5, [[13/9]], [[23/13]], and their [[octave complement]]s, and additional inconsistencies in the [[25-odd-limit]] include [[25/18]], [[25/23]], and their octave complements. Prime [[29/1|29]] is also accurate, though harmonic [[27/1|27]] is mapped inconsistently flat, causing many of its intervals to be inconsistent. Additionally, the flatness of 27 causes [[28/27]] to be mapped wider than [[27/26]], meaning 161edo is at most [[diamond monotone]] in the 25-odd-limit. | ||
As an equal temperament, 161et [[tempering out|tempers out]] the [[würschmidt comma]], 393216/390625, in the [[5-limit]]; [[3136/3125]], [[6144/6125]] and [[2401/2400]] in the [[7-limit]]; [[243/242]], [[441/440]], [[540/539]] and [[5632/5625]] in the [[11-limit]]; and [[351/350]], [[847/845]], [[1001/1000]], [[1188/1183]], [[1575/1573]] and [[1716/1715]] in the [[13-limit]]. It serves as the [[optimal patent val]] for the [[mintone]] temperament in the 5-, 7-, 11- and 13-limit. | |||
=== Prime harmonics === | === Prime harmonics === | ||
{{Harmonics in equal|161}} | {{Harmonics in equal|161}} | ||
| Line 12: | Line 13: | ||
=== Subsets and supersets === | === Subsets and supersets === | ||
Since 161 factors into 7 × 23, 161edo contains [[7edo]] and [[23edo]] as its subsets. | Since 161 factors into 7 × 23, 161edo contains [[7edo]] and [[23edo]] as its subsets. | ||
== Intervals == | |||
{{Interval table}} | |||
== Regular temperament properties == | == Regular temperament properties == | ||
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| [[Absurdity]] | | [[Absurdity]] | ||
|} | |} | ||
<nowiki />* [[Normal | <nowiki />* [[Normal forms #Equave-reduced-generator form|Octave-reduced form]], reduced to the first half-octave, and [[normal forms #Minimal-generator form|minimal form]] in parentheses if distinct | ||
[[Category:Mintone]] | [[Category:Mintone]] | ||
Latest revision as of 20:25, 10 April 2026
| ← 160edo | 161edo | 162edo → |
161 equal divisions of the octave (abbreviated 161edo or 161ed2), also called 161-tone equal temperament (161tet) or 161 equal temperament (161et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 161 equal parts of about 7.45 ¢ each. Each step represents a frequency ratio of 21/161, or the 161st root of 2.
Theory
161edo has a perfect fifth slightly sharp of that of 12edo, such that it maps the Pythagorean comma to one step. It approximates many of the low primes fairly well; however, it is only consistent to the 7-odd-limit, due to 10/9 being mapped too sharply from prime 5 being sharp, while 3 is flat. Nonetheless it does well for its size in higher limits, with the inconsistent intervals in the 23-odd-limit being 9/5, 13/9, 23/13, and their octave complements, and additional inconsistencies in the 25-odd-limit include 25/18, 25/23, and their octave complements. Prime 29 is also accurate, though harmonic 27 is mapped inconsistently flat, causing many of its intervals to be inconsistent. Additionally, the flatness of 27 causes 28/27 to be mapped wider than 27/26, meaning 161edo is at most diamond monotone in the 25-odd-limit.
As an equal temperament, 161et tempers out the würschmidt comma, 393216/390625, in the 5-limit; 3136/3125, 6144/6125 and 2401/2400 in the 7-limit; 243/242, 441/440, 540/539 and 5632/5625 in the 11-limit; and 351/350, 847/845, 1001/1000, 1188/1183, 1575/1573 and 1716/1715 in the 13-limit. It serves as the optimal patent val for the mintone temperament in the 5-, 7-, 11- and 13-limit.
Prime harmonics
| Harmonic | 2 | 3 | 5 | 7 | 11 | 13 | 17 | 19 | 23 | 29 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Error | Absolute (¢) | +0.00 | -1.33 | +1.26 | +0.12 | +0.23 | +1.71 | -0.61 | +0.62 | -2.19 | -1.01 | +2.79 |
| Relative (%) | +0.0 | -17.9 | +17.0 | +1.6 | +3.2 | +22.9 | -8.2 | +8.4 | -29.3 | -13.5 | +37.4 | |
| Steps (reduced) |
161 (0) |
255 (94) |
374 (52) |
452 (130) |
557 (74) |
596 (113) |
658 (14) |
684 (40) |
728 (84) |
782 (138) |
798 (154) | |
Subsets and supersets
Since 161 factors into 7 × 23, 161edo contains 7edo and 23edo as its subsets.
Intervals
| Steps | Cents | Approximate ratios | Ups and downs notation |
|---|---|---|---|
| 0 | 0 | 1/1 | D |
| 1 | 7.5 | ^D, ^^E♭♭ | |
| 2 | 14.9 | ^^D, ^3E♭♭ | |
| 3 | 22.4 | ^3D, ^4E♭♭ | |
| 4 | 29.8 | 56/55, 57/56, 58/57 | ^4D, ^5E♭♭ |
| 5 | 37.3 | 46/45, 47/46, 48/47 | ^5D, ^6E♭♭ |
| 6 | 44.7 | 39/38, 40/39 | ^6D, v7E♭ |
| 7 | 52.2 | 33/32, 34/33 | ^7D, v6E♭ |
| 8 | 59.6 | 29/28, 30/29 | v6D♯, v5E♭ |
| 9 | 67.1 | 26/25 | v5D♯, v4E♭ |
| 10 | 74.5 | 24/23, 47/45 | v4D♯, v3E♭ |
| 11 | 82 | 43/41 | v3D♯, vvE♭ |
| 12 | 89.4 | 20/19 | vvD♯, vE♭ |
| 13 | 96.9 | 37/35, 55/52 | vD♯, E♭ |
| 14 | 104.3 | 17/16 | D♯, ^E♭ |
| 15 | 111.8 | 16/15 | ^D♯, ^^E♭ |
| 16 | 119.3 | 15/14 | ^^D♯, ^3E♭ |
| 17 | 126.7 | ^3D♯, ^4E♭ | |
| 18 | 134.2 | 40/37 | ^4D♯, ^5E♭ |
| 19 | 141.6 | 38/35, 51/47 | ^5D♯, ^6E♭ |
| 20 | 149.1 | ^6D♯, v7E | |
| 21 | 156.5 | 23/21, 35/32 | ^7D♯, v6E |
| 22 | 164 | 11/10 | v6D𝄪, v5E |
| 23 | 171.4 | 32/29 | v5D𝄪, v4E |
| 24 | 178.9 | 41/37, 51/46 | v4D𝄪, v3E |
| 25 | 186.3 | 39/35, 49/44 | v3D𝄪, vvE |
| 26 | 193.8 | 19/17, 47/42 | vvD𝄪, vE |
| 27 | 201.2 | 55/49 | E |
| 28 | 208.7 | 35/31, 44/39 | ^E, ^^F♭ |
| 29 | 216.1 | 17/15 | ^^E, ^3F♭ |
| 30 | 223.6 | 33/29, 58/51 | ^3E, ^4F♭ |
| 31 | 231.1 | 8/7 | ^4E, ^5F♭ |
| 32 | 238.5 | 39/34 | ^5E, ^6F♭ |
| 33 | 246 | ^6E, v7F | |
| 34 | 253.4 | 22/19 | ^7E, v6F |
| 35 | 260.9 | 43/37, 50/43, 57/49 | v6E♯, v5F |
| 36 | 268.3 | v5E♯, v4F | |
| 37 | 275.8 | 34/29 | v4E♯, v3F |
| 38 | 283.2 | 33/28 | v3E♯, vvF |
| 39 | 290.7 | 58/49 | vvE♯, vF |
| 40 | 298.1 | 19/16 | F |
| 41 | 305.6 | 31/26, 37/31 | ^F, ^^G♭♭ |
| 42 | 313 | ^^F, ^3G♭♭ | |
| 43 | 320.5 | ^3F, ^4G♭♭ | |
| 44 | 328 | 29/24, 52/43 | ^4F, ^5G♭♭ |
| 45 | 335.4 | 17/14 | ^5F, ^6G♭♭ |
| 46 | 342.9 | 39/32, 50/41 | ^6F, v7G♭ |
| 47 | 350.3 | 49/40, 60/49 | ^7F, v6G♭ |
| 48 | 357.8 | 43/35 | v6F♯, v5G♭ |
| 49 | 365.2 | 21/17, 58/47 | v5F♯, v4G♭ |
| 50 | 372.7 | 31/25 | v4F♯, v3G♭ |
| 51 | 380.1 | v3F♯, vvG♭ | |
| 52 | 387.6 | 5/4 | vvF♯, vG♭ |
| 53 | 395 | 44/35, 49/39 | vF♯, G♭ |
| 54 | 402.5 | 29/23 | F♯, ^G♭ |
| 55 | 409.9 | 19/15 | ^F♯, ^^G♭ |
| 56 | 417.4 | 14/11 | ^^F♯, ^3G♭ |
| 57 | 424.8 | 23/18, 55/43 | ^3F♯, ^4G♭ |
| 58 | 432.3 | ^4F♯, ^5G♭ | |
| 59 | 439.8 | 49/38, 58/45 | ^5F♯, ^6G♭ |
| 60 | 447.2 | 22/17, 57/44 | ^6F♯, v7G |
| 61 | 454.7 | 13/10 | ^7F♯, v6G |
| 62 | 462.1 | 47/36 | v6F𝄪, v5G |
| 63 | 469.6 | 21/16 | v5F𝄪, v4G |
| 64 | 477 | 29/22 | v4F𝄪, v3G |
| 65 | 484.5 | 41/31, 45/34 | v3F𝄪, vvG |
| 66 | 491.9 | vvF𝄪, vG | |
| 67 | 499.4 | 4/3 | G |
| 68 | 506.8 | ^G, ^^A♭♭ | |
| 69 | 514.3 | 35/26, 39/29 | ^^G, ^3A♭♭ |
| 70 | 521.7 | 50/37 | ^3G, ^4A♭♭ |
| 71 | 529.2 | 19/14 | ^4G, ^5A♭♭ |
| 72 | 536.6 | 15/11 | ^5G, ^6A♭♭ |
| 73 | 544.1 | 26/19 | ^6G, v7A♭ |
| 74 | 551.6 | 11/8 | ^7G, v6A♭ |
| 75 | 559 | 29/21 | v6G♯, v5A♭ |
| 76 | 566.5 | 43/31 | v5G♯, v4A♭ |
| 77 | 573.9 | 39/28, 46/33 | v4G♯, v3A♭ |
| 78 | 581.4 | 7/5 | v3G♯, vvA♭ |
| 79 | 588.8 | 45/32, 52/37 | vvG♯, vA♭ |
| 80 | 596.3 | 24/17, 55/39 | vG♯, A♭ |
| 81 | 603.7 | 17/12 | G♯, ^A♭ |
| 82 | 611.2 | 37/26, 47/33 | ^G♯, ^^A♭ |
| 83 | 618.6 | 10/7 | ^^G♯, ^3A♭ |
| 84 | 626.1 | 33/23, 56/39 | ^3G♯, ^4A♭ |
| 85 | 633.5 | 49/34 | ^4G♯, ^5A♭ |
| 86 | 641 | 42/29, 55/38 | ^5G♯, ^6A♭ |
| 87 | 648.4 | 16/11 | ^6G♯, v7A |
| 88 | 655.9 | 19/13 | ^7G♯, v6A |
| 89 | 663.4 | 22/15 | v6G𝄪, v5A |
| 90 | 670.8 | 28/19 | v5G𝄪, v4A |
| 91 | 678.3 | 37/25 | v4G𝄪, v3A |
| 92 | 685.7 | 49/33, 52/35, 55/37, 58/39 | v3G𝄪, vvA |
| 93 | 693.2 | vvG𝄪, vA | |
| 94 | 700.6 | 3/2 | A |
| 95 | 708.1 | ^A, ^^B♭♭ | |
| 96 | 715.5 | ^^A, ^3B♭♭ | |
| 97 | 723 | 44/29 | ^3A, ^4B♭♭ |
| 98 | 730.4 | 32/21 | ^4A, ^5B♭♭ |
| 99 | 737.9 | 49/32 | ^5A, ^6B♭♭ |
| 100 | 745.3 | 20/13 | ^6A, v7B♭ |
| 101 | 752.8 | 17/11 | ^7A, v6B♭ |
| 102 | 760.2 | 45/29 | v6A♯, v5B♭ |
| 103 | 767.7 | v5A♯, v4B♭ | |
| 104 | 775.2 | 36/23 | v4A♯, v3B♭ |
| 105 | 782.6 | 11/7 | v3A♯, vvB♭ |
| 106 | 790.1 | 30/19 | vvA♯, vB♭ |
| 107 | 797.5 | 46/29 | vA♯, B♭ |
| 108 | 805 | 35/22 | A♯, ^B♭ |
| 109 | 812.4 | 8/5 | ^A♯, ^^B♭ |
| 110 | 819.9 | ^^A♯, ^3B♭ | |
| 111 | 827.3 | 50/31 | ^3A♯, ^4B♭ |
| 112 | 834.8 | 34/21, 47/29 | ^4A♯, ^5B♭ |
| 113 | 842.2 | ^5A♯, ^6B♭ | |
| 114 | 849.7 | 49/30 | ^6A♯, v7B |
| 115 | 857.1 | 41/25 | ^7A♯, v6B |
| 116 | 864.6 | 28/17 | v6A𝄪, v5B |
| 117 | 872 | 43/26, 48/29 | v5A𝄪, v4B |
| 118 | 879.5 | v4A𝄪, v3B | |
| 119 | 887 | v3A𝄪, vvB | |
| 120 | 894.4 | 52/31, 57/34 | vvA𝄪, vB |
| 121 | 901.9 | 32/19 | B |
| 122 | 909.3 | 49/29 | ^B, ^^C♭ |
| 123 | 916.8 | 56/33 | ^^B, ^3C♭ |
| 124 | 924.2 | 29/17 | ^3B, ^4C♭ |
| 125 | 931.7 | ^4B, ^5C♭ | |
| 126 | 939.1 | 43/25 | ^5B, ^6C♭ |
| 127 | 946.6 | 19/11 | ^6B, v7C |
| 128 | 954 | ^7B, v6C | |
| 129 | 961.5 | v6B♯, v5C | |
| 130 | 968.9 | 7/4 | v5B♯, v4C |
| 131 | 976.4 | 51/29, 58/33 | v4B♯, v3C |
| 132 | 983.9 | 30/17 | v3B♯, vvC |
| 133 | 991.3 | 39/22, 55/31 | vvB♯, vC |
| 134 | 998.8 | 57/32 | C |
| 135 | 1006.2 | 34/19 | ^C, ^^D♭♭ |
| 136 | 1013.7 | ^^C, ^3D♭♭ | |
| 137 | 1021.1 | ^3C, ^4D♭♭ | |
| 138 | 1028.6 | 29/16 | ^4C, ^5D♭♭ |
| 139 | 1036 | 20/11 | ^5C, ^6D♭♭ |
| 140 | 1043.5 | 42/23 | ^6C, v7D♭ |
| 141 | 1050.9 | ^7C, v6D♭ | |
| 142 | 1058.4 | 35/19 | v6C♯, v5D♭ |
| 143 | 1065.8 | 37/20 | v5C♯, v4D♭ |
| 144 | 1073.3 | v4C♯, v3D♭ | |
| 145 | 1080.7 | 28/15 | v3C♯, vvD♭ |
| 146 | 1088.2 | 15/8 | vvC♯, vD♭ |
| 147 | 1095.7 | 32/17 | vC♯, D♭ |
| 148 | 1103.1 | C♯, ^D♭ | |
| 149 | 1110.6 | 19/10 | ^C♯, ^^D♭ |
| 150 | 1118 | ^^C♯, ^3D♭ | |
| 151 | 1125.5 | 23/12 | ^3C♯, ^4D♭ |
| 152 | 1132.9 | 25/13 | ^4C♯, ^5D♭ |
| 153 | 1140.4 | 29/15, 56/29 | ^5C♯, ^6D♭ |
| 154 | 1147.8 | 33/17 | ^6C♯, v7D |
| 155 | 1155.3 | 39/20 | ^7C♯, v6D |
| 156 | 1162.7 | 45/23, 47/24 | v6C𝄪, v5D |
| 157 | 1170.2 | 55/28, 57/29 | v5C𝄪, v4D |
| 158 | 1177.6 | v4C𝄪, v3D | |
| 159 | 1185.1 | v3C𝄪, vvD | |
| 160 | 1192.5 | vvC𝄪, vD | |
| 161 | 1200 | 2/1 | D |
Regular temperament properties
| Subgroup | Comma list | Mapping | Optimal 8ve stretch (¢) |
Tuning error | |
|---|---|---|---|---|---|
| Absolute (¢) | Relative (%) | ||||
| 2.3 | [-255 161⟩ | [⟨161 255]] | +0.421 | 0.421 | 5.65 |
| 2.3.5 | 393216/390625, [-17 21 -7⟩ | [⟨161 255 374]] | +0.099 | 0.570 | 7.65 |
| 2.3.5.7 | 2401/2400, 3136/3125, 177147/175000 | [⟨161 255 374 452]] | +0.064 | 0.498 | 6.67 |
| 2.3.5.7.11 | 243/242, 441/440, 3136/3125, 35937/35840 | [⟨161 255 374 452 557]] | +0.037 | 0.448 | 6.01 |
| 2.3.5.7.11.13 | 243/242, 351/350, 441/440, 847/845, 3136/3125 | [⟨161 255 374 452 557 596]] | −0.046 | 0.449 | 6.03 |
| 2.3.5.7.11.13.17 | 243/242, 351/350, 441/440, 561/560, 847/845, 1089/1088 | [⟨161 255 374 452 557 596 658]] | −0.018 | 0.422 | 5.66 |
| 2.3.5.7.11.13.17.19 | 243/242, 324/323, 351/350, 441/440, 456/455, 495/494, 513/512 | [⟨161 255 374 452 557 596 658 684]] | −0.034 | 0.397 | 5.32 |
- 161et has a lower absolute error than any previous equal temperaments in the 19-limit, even though it is inconsistent in the corresponding odd limit. The same subgroup is only better tuned by 183edo.
Rank-2 temperaments
| Periods per 8ve |
Generator* | Cents* | Associated ratio* |
Temperaments |
|---|---|---|---|---|
| 1 | 15\161 | 111.80 | 16/15 | Vavoom |
| 1 | 16\161 | 119.25 | 15/14 | Septidiasemi |
| 1 | 17\161 | 126.71 | 14/13 | Mowglic |
| 1 | 25\161 | 186.34 | 10/9 | Mintone |
| 1 | 26\161 | 193.79 | 28/25 | Hemiwürschmidt |
| 1 | 38\161 | 283.23 | 33/28 | Neominor (161f) |
| 1 | 52\161 | 387.58 | 5/4 | Würschmidt (5-limit) |
| 1 | 79\161 | 588.82 | 45/32 | Aufo |
| 7 | 67\161 (2\161) |
499.38 (14.91) |
4/3 (81/80) |
Absurdity |
* Octave-reduced form, reduced to the first half-octave, and minimal form in parentheses if distinct