209edt
209 equal divisions of the tritave, perfect twelfth, or 3rd harmonic (abbreviated 209edt or 209ed3), is a nonoctave tuning system that divides the interval of 3/1 into 209 equal parts of about 9.1 ¢ each. Each step represents a frequency ratio of 31/209, or the 209th root of 3.
| ← 208edt | 209edt | 210edt → |
Since 209 factors into 11 × 19, 209edt has 11edt and 19edt as subsets; it inherits its mapping of the 11th harmonic from the former and the 17th (along with the octave, corresponding to 19edt being a close octave stretch of 12edo) from the latter. It otherwise represents a very strong system in the 19-limit (even including prime 2), being the sum of 78edt which has a flat tendency in the 19-limit and 131edt which has a slight sharp tendency. Its most accurate simple intervals are 7/5, 11/5, and 17/9, all of which it approximates to within about 0.1 cents.
Intervals
| Steps | Cents | Hekts | Approximate ratios |
|---|---|---|---|
| 0 | 0 | 0 | 1/1 |
| 1 | 9.1 | 6.22 | |
| 2 | 18.2 | 12.44 | |
| 3 | 27.3 | 18.66 | 63/62, 66/65 |
| 4 | 36.4 | 24.88 | 47/46 |
| 5 | 45.5 | 31.1 | 38/37, 39/38 |
| 6 | 54.6 | 37.32 | 65/63 |
| 7 | 63.7 | 43.54 | 28/27 |
| 8 | 72.8 | 49.76 | 49/47 |
| 9 | 81.9 | 55.98 | 65/62 |
| 10 | 91 | 62.2 | 39/37 |
| 11 | 100.1 | 68.42 | |
| 12 | 109.2 | 74.64 | 33/31, 49/46 |
| 13 | 118.3 | 80.86 | |
| 14 | 127.4 | 87.08 | 14/13 |
| 15 | 136.5 | 93.3 | |
| 16 | 145.6 | 99.52 | 37/34, 62/57 |
| 17 | 154.7 | 105.74 | |
| 18 | 163.8 | 111.96 | |
| 19 | 172.91 | 118.18 | 21/19 |
| 20 | 182.01 | 124.4 | 10/9 |
| 21 | 191.11 | 130.62 | 48/43 |
| 22 | 200.21 | 136.84 | 46/41, 55/49 |
| 23 | 209.31 | 143.06 | 35/31, 44/39 |
| 24 | 218.41 | 149.28 | 42/37 |
| 25 | 227.51 | 155.5 | 57/50, 65/57 |
| 26 | 236.61 | 161.72 | 39/34, 47/41 |
| 27 | 245.71 | 167.94 | |
| 28 | 254.81 | 174.16 | 22/19, 51/44 |
| 29 | 263.91 | 180.38 | |
| 30 | 273.01 | 186.6 | 41/35, 55/47 |
| 31 | 282.11 | 192.82 | 20/17 |
| 32 | 291.21 | 199.04 | |
| 33 | 300.31 | 205.26 | 44/37 |
| 34 | 309.41 | 211.48 | 49/41, 55/46 |
| 35 | 318.51 | 217.7 | |
| 36 | 327.61 | 223.92 | 29/24 |
| 37 | 336.71 | 230.14 | 17/14 |
| 38 | 345.81 | 236.36 | |
| 39 | 354.91 | 242.58 | 27/22, 70/57 |
| 40 | 364.01 | 248.8 | 37/30 |
| 41 | 373.11 | 255.02 | 31/25 |
| 42 | 382.21 | 261.24 | |
| 43 | 391.31 | 267.46 | |
| 44 | 400.41 | 273.68 | 63/50 |
| 45 | 409.51 | 279.9 | 19/15 |
| 46 | 418.61 | 286.12 | |
| 47 | 427.71 | 292.34 | |
| 48 | 436.81 | 298.56 | |
| 49 | 445.91 | 304.78 | 22/17 |
| 50 | 455.01 | 311 | 13/10 |
| 51 | 464.11 | 317.22 | 17/13 |
| 52 | 473.21 | 323.44 | 46/35 |
| 53 | 482.31 | 329.67 | 37/28 |
| 54 | 491.41 | 335.89 | |
| 55 | 500.51 | 342.11 | |
| 56 | 509.61 | 348.33 | 47/35, 51/38, 55/41 |
| 57 | 518.72 | 354.55 | 27/20, 58/43 |
| 58 | 527.82 | 360.77 | 19/14 |
| 59 | 536.92 | 366.99 | 15/11 |
| 60 | 546.02 | 373.21 | 37/27 |
| 61 | 555.12 | 379.43 | 51/37, 62/45 |
| 62 | 564.22 | 385.65 | 18/13 |
| 63 | 573.32 | 391.87 | 39/28 |
| 64 | 582.42 | 398.09 | 7/5 |
| 65 | 591.52 | 404.31 | 38/27 |
| 66 | 600.62 | 410.53 | |
| 67 | 609.72 | 416.75 | |
| 68 | 618.82 | 422.97 | |
| 69 | 627.92 | 429.19 | |
| 70 | 637.02 | 435.41 | 13/9 |
| 71 | 646.12 | 441.63 | 45/31 |
| 72 | 655.22 | 447.85 | 54/37 |
| 73 | 664.32 | 454.07 | 69/47 |
| 74 | 673.42 | 460.29 | 31/21 |
| 75 | 682.52 | 466.51 | 43/29, 46/31 |
| 76 | 691.62 | 472.73 | |
| 77 | 700.72 | 478.95 | |
| 78 | 709.82 | 485.17 | |
| 79 | 718.92 | 491.39 | 50/33 |
| 80 | 728.02 | 497.61 | |
| 81 | 737.12 | 503.83 | |
| 82 | 746.22 | 510.05 | 20/13 |
| 83 | 755.32 | 516.27 | 65/42 |
| 84 | 764.42 | 522.49 | 14/9 |
| 85 | 773.52 | 528.71 | |
| 86 | 782.62 | 534.93 | 11/7 |
| 87 | 791.72 | 541.15 | 30/19, 49/31 |
| 88 | 800.82 | 547.37 | 27/17 |
| 89 | 809.92 | 553.59 | |
| 90 | 819.02 | 559.81 | |
| 91 | 828.12 | 566.03 | 50/31 |
| 92 | 837.22 | 572.25 | 60/37 |
| 93 | 846.32 | 578.47 | 44/27 |
| 94 | 855.42 | 584.69 | 41/25 |
| 95 | 864.53 | 590.91 | 28/17 |
| 96 | 873.63 | 597.13 | |
| 97 | 882.73 | 603.35 | |
| 98 | 891.83 | 609.57 | 72/43 |
| 99 | 900.93 | 615.79 | 37/22, 69/41 |
| 100 | 910.03 | 622.01 | 22/13 |
| 101 | 919.13 | 628.23 | 17/10 |
| 102 | 928.23 | 634.45 | |
| 103 | 937.33 | 640.67 | |
| 104 | 946.43 | 646.89 | 19/11 |
| 105 | 955.53 | 653.11 | 33/19 |
| 106 | 964.63 | 659.33 | |
| 107 | 973.73 | 665.55 | |
| 108 | 982.83 | 671.77 | 30/17 |
| 109 | 991.93 | 677.99 | 39/22, 55/31 |
| 110 | 1001.03 | 684.21 | 41/23, 66/37 |
| 111 | 1010.13 | 690.43 | 43/24, 52/29 |
| 112 | 1019.23 | 696.65 | |
| 113 | 1028.33 | 702.87 | |
| 114 | 1037.43 | 709.09 | 51/28 |
| 115 | 1046.53 | 715.31 | |
| 116 | 1055.63 | 721.53 | 46/25 |
| 117 | 1064.73 | 727.75 | 37/20 |
| 118 | 1073.83 | 733.97 | |
| 119 | 1082.93 | 740.19 | |
| 120 | 1092.03 | 746.41 | 47/25, 62/33 |
| 121 | 1101.13 | 752.63 | 17/9 |
| 122 | 1110.23 | 758.85 | 19/10 |
| 123 | 1119.33 | 765.07 | 21/11 |
| 124 | 1128.43 | 771.29 | |
| 125 | 1137.53 | 777.51 | 27/14 |
| 126 | 1146.63 | 783.73 | |
| 127 | 1155.73 | 789.95 | 39/20 |
| 128 | 1164.83 | 796.17 | 49/25 |
| 129 | 1173.93 | 802.39 | 65/33 |
| 130 | 1183.03 | 808.61 | |
| 131 | 1192.13 | 814.83 | |
| 132 | 1201.23 | 821.05 | |
| 133 | 1210.34 | 827.27 | |
| 134 | 1219.44 | 833.49 | |
| 135 | 1228.54 | 839.71 | 63/31 |
| 136 | 1237.64 | 845.93 | 47/23 |
| 137 | 1246.74 | 852.15 | 37/18 |
| 138 | 1255.84 | 858.37 | 31/15 |
| 139 | 1264.94 | 864.59 | 27/13 |
| 140 | 1274.04 | 870.81 | |
| 141 | 1283.14 | 877.03 | |
| 142 | 1292.24 | 883.25 | |
| 143 | 1301.34 | 889.47 | 70/33 |
| 144 | 1310.44 | 895.69 | |
| 145 | 1319.54 | 901.91 | 15/7 |
| 146 | 1328.64 | 908.13 | 28/13 |
| 147 | 1337.74 | 914.35 | 13/6 |
| 148 | 1346.84 | 920.57 | 37/17 |
| 149 | 1355.94 | 926.79 | |
| 150 | 1365.04 | 933.01 | 11/5 |
| 151 | 1374.14 | 939.23 | 42/19 |
| 152 | 1383.24 | 945.45 | 20/9 |
| 153 | 1392.34 | 951.67 | 38/17 |
| 154 | 1401.44 | 957.89 | |
| 155 | 1410.54 | 964.11 | 70/31 |
| 156 | 1419.64 | 970.33 | |
| 157 | 1428.74 | 976.56 | |
| 158 | 1437.84 | 982.78 | 39/17 |
| 159 | 1446.94 | 989 | 30/13 |
| 160 | 1456.04 | 995.22 | 51/22 |
| 161 | 1465.14 | 1001.44 | |
| 162 | 1474.24 | 1007.66 | |
| 163 | 1483.34 | 1013.88 | |
| 164 | 1492.44 | 1020.1 | 45/19 |
| 165 | 1501.54 | 1026.32 | 50/21 |
| 166 | 1510.64 | 1032.54 | |
| 167 | 1519.74 | 1038.76 | |
| 168 | 1528.84 | 1044.98 | |
| 169 | 1537.94 | 1051.2 | |
| 170 | 1547.04 | 1057.42 | 22/9 |
| 171 | 1556.15 | 1063.64 | |
| 172 | 1565.25 | 1069.86 | 42/17 |
| 173 | 1574.35 | 1076.08 | 72/29 |
| 174 | 1583.45 | 1082.3 | |
| 175 | 1592.55 | 1088.52 | |
| 176 | 1601.65 | 1094.74 | |
| 177 | 1610.75 | 1100.96 | |
| 178 | 1619.85 | 1107.18 | 51/20 |
| 179 | 1628.95 | 1113.4 | |
| 180 | 1638.05 | 1119.62 | |
| 181 | 1647.15 | 1125.84 | 44/17, 57/22 |
| 182 | 1656.25 | 1132.06 | |
| 183 | 1665.35 | 1138.28 | 34/13 |
| 184 | 1674.45 | 1144.5 | 50/19 |
| 185 | 1683.55 | 1150.72 | 37/14 |
| 186 | 1692.65 | 1156.94 | |
| 187 | 1701.75 | 1163.16 | |
| 188 | 1710.85 | 1169.38 | 43/16 |
| 189 | 1719.95 | 1175.6 | 27/10 |
| 190 | 1729.05 | 1181.82 | 19/7 |
| 191 | 1738.15 | 1188.04 | |
| 192 | 1747.25 | 1194.26 | |
| 193 | 1756.35 | 1200.48 | |
| 194 | 1765.45 | 1206.7 | |
| 195 | 1774.55 | 1212.92 | 39/14 |
| 196 | 1783.65 | 1219.14 | |
| 197 | 1792.75 | 1225.36 | 31/11 |
| 198 | 1801.85 | 1231.58 | |
| 199 | 1810.95 | 1237.8 | 37/13 |
| 200 | 1820.05 | 1244.02 | |
| 201 | 1829.15 | 1250.24 | |
| 202 | 1838.25 | 1256.46 | |
| 203 | 1847.35 | 1262.68 | |
| 204 | 1856.45 | 1268.9 | 38/13 |
| 205 | 1865.55 | 1275.12 | |
| 206 | 1874.65 | 1281.34 | 62/21, 65/22 |
| 207 | 1883.75 | 1287.56 | |
| 208 | 1892.85 | 1293.78 | |
| 209 | 1901.96 | 1300 | 3/1 |
Harmonics
| Harmonic | 2 | 3 | 5 | 7 | 11 | 13 | 17 | 19 | 23 | |
|---|---|---|---|---|---|---|---|---|---|---|
| Error | Absolute (¢) | +1.23 | +0.00 | -1.63 | -1.73 | -1.60 | +0.40 | +0.09 | -1.37 | -4.52 |
| Relative (%) | +13.6 | +0.0 | -17.9 | -19.0 | -17.6 | +4.4 | +0.9 | -15.0 | -49.6 | |
| Steps (reduced) |
132 (132) |
209 (0) |
306 (97) |
370 (161) |
456 (38) |
488 (70) |
539 (121) |
560 (142) |
596 (178) | |
| Harmonic | 25 | 27 | 29 | 31 | 33 | 35 | 37 | 39 | 41 | 43 | 45 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Error | Absolute (¢) | -3.27 | +0.00 | +3.69 | -2.56 | -1.60 | -3.36 | +0.54 | +0.40 | -4.28 | +4.27 | -1.63 |
| Relative (%) | -35.9 | +0.0 | +40.6 | -28.2 | -17.6 | -36.9 | +5.9 | +4.4 | -47.0 | +46.9 | -17.9 | |
| Steps (reduced) |
612 (194) |
627 (0) |
641 (14) |
653 (26) |
665 (38) |
676 (49) |
687 (60) |
697 (70) |
706 (79) |
716 (89) |
724 (97) | |