68edo: Difference between revisions
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The '''68 equal temperament''', often abbreviated '''68-tET''', '''68-EDO''', or '''68-ET''', is the scale derived by dividing the octave into 68 equally-sized steps. Each step represents a frequency ratio of 17.65 cents | The '''68 equal temperament''', often abbreviated '''68-tET''', '''68-EDO''', or '''68-ET''', is the scale derived by dividing the octave into 68 equally-sized steps. Each step represents a frequency ratio of 17.65 cents. | ||
== Theory == | |||
68edo's step is half of the step size of [[34edo]], which does well in the 5-limit but not so well in the 7-limit, and one quarter the size of [[17edo]], which does well in the [[3-limit]], but not so well in the [[5-limit]]. The luck continues: 68 is a strong [[7-limit]] system, but does not do as well for in [[11-limit]]; though it's certainly usable for that purpose, it does not represent the 11-limit diamond [[consistent]]ly. | |||
As a 7-limit system it tempers out [[Diaschisma|2048/2025]], [[245/243]], 4000/3969, [[15625/15552]], [[3136/3125]], [[6144/6125]] and [[2401/2400]]. It supports [[octacot]], [[shrutar]], [[hemiwürschmidt]], [[hemikleismic]], [[clyde]] and [[neptune]] temperaments, and supplies the [[optimal patent val]] for 11-limit [[hemikleismic]]. It is a sharp-tending system, with the third, fifth and seventh harmonics all sharp. | As a 7-limit system it tempers out [[Diaschisma|2048/2025]], [[245/243]], 4000/3969, [[15625/15552]], [[3136/3125]], [[6144/6125]] and [[2401/2400]]. It supports [[octacot]], [[shrutar]], [[hemiwürschmidt]], [[hemikleismic]], [[clyde]] and [[neptune]] temperaments, and supplies the [[optimal patent val]] for 11-limit [[hemikleismic]]. It is a sharp-tending system, with the third, fifth and seventh harmonics all sharp. | ||
=== Prime harmonics === | |||
{{Primes in edo|68}} | |||
== Intervals == | == Intervals == | ||
| Line 7: | Line 13: | ||
! Degrees | ! Degrees | ||
! Cents | ! Cents | ||
! Approximate Ratios | |||
|- | |- | ||
|0 | | 0 | ||
|0. | | 0.00 | ||
| 1/1 | |||
|- | |- | ||
|1 | | 1 | ||
|17. | | 17.65 | ||
| 64/63, 126/125, 225/224 | |||
|- | |- | ||
|2 | | 2 | ||
|35. | | 35.29 | ||
| 81/80, 49/48, 50/49 | |||
|- | |- | ||
|3 | | 3 | ||
|52. | | 52.94 | ||
| 28/27, 36/35, 33/32 | |||
|- | |- | ||
|4 | | 4 | ||
|70. | | 70.59 | ||
| 25/24, ''22/21'' | |||
|- | |- | ||
|5 | | 5 | ||
|88. | | 88.24 | ||
| 21/20, 19/18, 20/19 | |||
|- | |- | ||
|6 | | 6 | ||
|105. | | 105.88 | ||
| 16/15, 17/16, 18/17 | |||
|- | |- | ||
|7 | | 7 | ||
|123. | | 123.53 | ||
| 15/14, 14/13 | |||
|- | |- | ||
|8 | | 8 | ||
|141. | | 141.18 | ||
| 13/12 | |||
|- | |- | ||
|9 | | 9 | ||
|158. | | 158.82 | ||
| 12/11, 11/10 | |||
|- | |- | ||
|10 | | 10 | ||
|176. | | 176.47 | ||
| 10/9 | |||
|- | |- | ||
|11 | | 11 | ||
|194. | | 194.12 | ||
| 28/25, 19/17 | |||
|- | |- | ||
|12 | | 12 | ||
|211. | | 211.76 | ||
| 9/8 | |||
|- | |- | ||
|13 | | 13 | ||
|229. | | 229.41 | ||
| 8/7 | |||
|- | |- | ||
|14 | | 14 | ||
|247. | | 247.06 | ||
| 15/13 | |||
|- | |- | ||
|15 | | 15 | ||
|264. | | 264.71 | ||
| 7/6 | |||
|- | |- | ||
|16 | | 16 | ||
|282. | | 282.35 | ||
| 20/17 | |||
|- | |- | ||
|17 | | 17 | ||
|300. | | 300.00 | ||
| ''13/11'', 19/16 | |||
|- | |- | ||
|18 | | 18 | ||
|317. | | 317.65 | ||
| 6/5 | |||
|- | |- | ||
|19 | | 19 | ||
|335. | | 335.29 | ||
| ''11/9'', 40/33, 17/14 | |||
|- | |- | ||
|20 | | 20 | ||
|352. | | 352.94 | ||
| 16/13, ''39/32'' | |||
|- | |- | ||
|21 | | 21 | ||
|370. | | 370.59 | ||
| ''27/22'', 26/21, 21/17 | |||
|- | |- | ||
|22 | | 22 | ||
|388. | | 388.24 | ||
| 5/4 | |||
|- | |- | ||
|23 | | 23 | ||
|405. | | 405.88 | ||
| 24/19, 19/15 | |||
|- | |- | ||
|24 | | 24 | ||
|423. | | 423.53 | ||
| 14/11 | |||
|- | |- | ||
|25 | | 25 | ||
|441. | | 441.18 | ||
| 9/7 | |||
|- | |- | ||
|26 | | 26 | ||
|458. | | 458.82 | ||
| 13/10, 17/13 | |||
|- | |- | ||
|27 | | 27 | ||
|476. | | 476.47 | ||
| 21/16 | |||
|- | |- | ||
|28 | | 28 | ||
|494. | | 494.12 | ||
| 4/3 | |||
|- | |- | ||
|29 | | 29 | ||
|511. | | 511.76 | ||
| 75/56 | |||
|- | |- | ||
|30 | | 30 | ||
|529. | | 529.41 | ||
| 27/20, 19/14 | |||
|- | |- | ||
|31 | | 31 | ||
|547. | | 547.06 | ||
| 11/8, ''15/11'' | |||
|- | |- | ||
|32 | | 32 | ||
|564. | | 564.71 | ||
| 25/18, 18/13, 26/19 | |||
|- | |- | ||
|33 | | 33 | ||
|582. | | 582.35 | ||
| 7/5 | |||
|- | |- | ||
|34 | | 34 | ||
|600. | | 600.00 | ||
| 17/12, 24/17 | |||
|- | |- | ||
|35 | | 35 | ||
|617. | | 617.65 | ||
| 10/7 | |||
|- | |- | ||
|36 | | 36 | ||
|635. | | 635.29 | ||
| 36/25, 13/9, 19/13 | |||
|- | |- | ||
|37 | | 37 | ||
|652. | | 652.94 | ||
| 16/11, ''22/15'' | |||
|- | |- | ||
|38 | | 38 | ||
|670. | | 670.59 | ||
| 40/27, 28/19 | |||
|- | |- | ||
|39 | | 39 | ||
|688. | | 688.24 | ||
| 112/75 | |||
|- | |- | ||
|40 | | 40 | ||
|705. | | 705.88 | ||
| 3/2 | |||
|- | |- | ||
|41 | | 41 | ||
|723. | | 723.53 | ||
| 32/21 | |||
|- | |- | ||
|42 | | 42 | ||
|741. | | 741.18 | ||
| 16/13, 26/17 | |||
|- | |- | ||
|43 | | 43 | ||
|758. | | 758.82 | ||
| 14/9 | |||
|- | |- | ||
|44 | | 44 | ||
|776. | | 776.47 | ||
| 11/7 | |||
|- | |- | ||
|45 | | 45 | ||
|794. | | 794.12 | ||
| 19/12, 30/19 | |||
|- | |- | ||
|46 | | 46 | ||
|811. | | 811.76 | ||
| 8/5 | |||
|- | |- | ||
|47 | | 47 | ||
|829. | | 829.41 | ||
| ''44/27'', 21/13, 34/21 | |||
|- | |- | ||
|48 | | 48 | ||
|847. | | 847.06 | ||
| 13/8, ''64/39'' | |||
|- | |- | ||
|49 | | 49 | ||
|864. | | 864.71 | ||
| ''18/11'', 33/20, 28/17 | |||
|- | |- | ||
|50 | | 50 | ||
|882. | | 882.35 | ||
| 5/3 | |||
|- | |- | ||
|51 | | 51 | ||
|900. | | 900.00 | ||
| ''22/13'', 32/19 | |||
|- | |- | ||
|52 | | 52 | ||
|917. | | 917.65 | ||
| 17/10 | |||
|- | |- | ||
|53 | | 53 | ||
|935. | | 935.29 | ||
| 12/7 | |||
|- | |- | ||
|54 | | 54 | ||
|952. | | 952.94 | ||
| 26/15 | |||
|- | |- | ||
|55 | | 55 | ||
|970. | | 970.59 | ||
| 7/4 | |||
|- | |- | ||
|56 | | 56 | ||
|988. | | 988.24 | ||
| 16/9 | |||
|- | |- | ||
|57 | | 57 | ||
|1005. | | 1005.88 | ||
| 25/14, 34/19 | |||
|- | |- | ||
|58 | | 58 | ||
|1023. | | 1023.53 | ||
| 9/5 | |||
|- | |- | ||
|59 | | 59 | ||
|1041. | | 1041.18 | ||
| 11/6, 20/11 | |||
|- | |- | ||
|60 | | 60 | ||
|1058. | | 1058.82 | ||
| 24/13 | |||
|- | |- | ||
|61 | | 61 | ||
|1076. | | 1076.47 | ||
| 28/15, 13/7 | |||
|- | |- | ||
|62 | | 62 | ||
|1094. | | 1094.12 | ||
| 15/8, 32/17, 17/9 | |||
|- | |- | ||
|63 | | 63 | ||
|1111. | | 1111.76 | ||
| 40/21, 36/19, 19/10 | |||
|- | |- | ||
|64 | | 64 | ||
|1129. | | 1129.41 | ||
| 48/25, ''21/11'' | |||
|- | |- | ||
|65 | | 65 | ||
|1147. | | 1147.06 | ||
| 27/14, 35/18, 64/33 | |||
|- | |- | ||
|66 | | 66 | ||
|1164. | | 1164.71 | ||
| 160/81, 96/49, 49/25 | |||
|- | |- | ||
|67 | | 67 | ||
|1182. | | 1182.35 | ||
| 63/32, 125/64, 448/225 | |||
|- | |- | ||
|68 | | 68 | ||
|1200. | | 1200.00 | ||
| 2/1 | |||
|} | |} | ||
| Line 231: | Line 307: | ||
Inverse half octave: 4 4 7 4 4 4 4 7 4 4 7 4 4 4 4 7 | Inverse half octave: 4 4 7 4 4 4 4 7 4 4 7 4 4 4 4 7 | ||
[[Category:Equal divisions of the octave]] | |||
[[Category:Clyde]] | [[Category:Clyde]] | ||
[[Category:Hemikleismic]] | [[Category:Hemikleismic]] | ||
[[Category:Hemiwürschmidt]] | [[Category:Hemiwürschmidt]] | ||
[[Category:Neptune]] | [[Category:Neptune]] | ||
[[Category:Octacot]] | [[Category:Octacot]] | ||
[[Category:Shrutar]] | |||
[[Category:Quartismic]] | [[Category:Quartismic]] | ||