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'''Intergan''' is a set of temperaments related to 24edo semiquartal. The term is short for "interseptimal Ganassi," after 12edo's 2.3.17.19 Ganassi temperament. It seeks to cover all of the notable concordances generated by a meantone-range semifourth. | '''Intergan''' is a set of temperaments related to 24edo semiquartal. The term is short for "interseptimal Ganassi," after 12edo's 2.3.17.19 Ganassi temperament. It seeks to cover all of the notable concordances generated by a meantone-range semifourth. It was specified in a [https://groundfault.tumblr.com/post/715804797472800768/the-best-semiquartal-probably 2023 Tumblr post]. | ||
* The most basic version is 2.3.11.13/5.17.19 5&24. 4/3 is split into two semifourths most simply represented by 15/13, and 22/17 is equated to 13/10 and 22/19 is equated to 15/13. It | == Semiquartal == | ||
* The most basic version is 2.3.11.13/5.17.19 5&24. 4/3 is split into two semifourths most simply represented by 15/13, and 22/17 is equated to 13/10 and 22/19 is equated to 15/13. It features the remarkably simple 10:13:15 ultramajor triad and its retroversion found in Island temperaments, along with the 16:19:22 +1+1 sub-diminished triad and 16:19:24:27 +3+5+3 minor add6 tetrad. 11:12:17:19 is present, although this adding 13, 14, or 15 to the subgroup will significantly improve its usefulness. | |||
* Tempering out 81/80 is somewhat obvious, resulting in 2.3.5.11.13.17.19 5&24. | * Tempering out 81/80 is somewhat obvious, resulting in 2.3.5.11.13.17.19 5&24. | ||
* Primes 31 and 37 are also obvious to add, equating 37/32 to 22/19 and 37/31 to 19/16, resulting in 2.3.5.11.13.17.19.31.37 5&24. 67edo is roughly optimal due to its very mild meantone fourth being split in half. The 2.31.37 restriction is highly accurate in 43edo. | * Primes 31 and 37 are also obvious to add, equating 37/32 to 22/19 and 37/31 to 19/16, resulting in 2.3.5.11.13.17.19.31.37 5&24. 67edo is roughly optimal due to its very mild meantone fourth being split in half. The 2.31.37 restriction is highly accurate in 43edo. | ||
* Primes 7, 23, and 29 are all more difficult to map due to their complexity, although their difficulty is in ascending order. They are more easily reached by splitting the semifourth generator in half in a manner similar to Negri. | * Primes 7, 23, and 29 are all more difficult to map due to their complexity, although their difficulty is in ascending order. They are more easily reached by splitting the semifourth generator in half in a manner similar to Negri. | ||
{| class="wikitable" | |||
|+Semiquartal Intergan, 14\67 generator, 37-limit patent val, 37-odd-limit | |||
!Gens | |||
!Cents | |||
!JI Interpretations | |||
|- | |||
!33 | |||
|1075 | |||
|28/15 13/7 54/29 58/31 | |||
|- | |||
!32 | |||
|824 | |||
|21/13 29/18 37/23 | |||
|- | |||
!31 | |||
|573 | |||
|32/23 40/29 7/5 46/33 | |||
|- | |||
!30 | |||
|322 | |||
|23/19 25/21 29/24 | |||
|- | |||
!29 | |||
|72 | |||
|24/23 28/27 30/29 21/20 23/22 | |||
|- | |||
!28 | |||
|1021 | |||
|56/31 52/29 25/14 '''''29/16''''' | |||
|- | |||
!27 | |||
|770 | |||
|14/9 36/23 58/37 | |||
|- | |||
!26 | |||
|519 | |||
|34/25 42/31 23/17 31/23 35/26 | |||
|- | |||
!25 | |||
|269 | |||
|7/6 27/23 | |||
|- | |||
!24 | |||
|18 | |||
| | |||
|- | |||
!23 | |||
|967 | |||
|40/23 '''''7/4''''' 44/25 50/29 58/33 | |||
|- | |||
!22 | |||
|716 | |||
|56/37 38/25 29/19 | |||
|- | |||
!21 | |||
|466 | |||
|30/23 17/13 21/16 46/35 29/22 33/25 35/27 | |||
|- | |||
!20 | |||
|215 | |||
|26/23 17/15 42/37 35/31 | |||
|- | |||
!19 | |||
|1164 | |||
|35/18 | |||
|- | |||
!18 | |||
|913 | |||
|56/33 22/13 17/10 29/17 | |||
|- | |||
!17 | |||
|663 | |||
|28/19 22/15 19/13 35/24 37/25 | |||
|- | |||
!16 | |||
|412 | |||
|32/25 14/11 34/27 19/15 33/26 | |||
|- | |||
!15 | |||
|161 | |||
|11/10 34/31 21/19 23/21 25/23 35/32 | |||
|- | |||
!14 | |||
|1110 | |||
|48/25 17/9 19/10 21/11 70/37 | |||
|- | |||
!13 | |||
|860 | |||
|28/17 44/27 23/14 58/35 33/20 | |||
|- | |||
!12 | |||
|609 | |||
|36/25 44/31 17/12 38/27 37/26 | |||
|- | |||
!11 | |||
|358 | |||
|16/13 11/9 38/31 21/17 31/25 37/30 | |||
|- | |||
!10 | |||
|107 | |||
|16/15 '''''17/16''''' 19/18 27/25 33/31 35/33 | |||
|- | |||
!9 | |||
|1057 | |||
|24/13 11/6 68/37 35/19 37/20 | |||
|- | |||
!8 | |||
|806 | |||
|8/5 19/12 46/29 35/22 | |||
|- | |||
!7 | |||
|555 | |||
|18/13 '''''11/8''''' 29/21 37/27 | |||
|- | |||
!6 | |||
|304 | |||
|32/27 6/5 44/37 '''''19/16''''' 31/26 37/31 | |||
|- | |||
!5 | |||
|54 | |||
|32/31 26/25 34/33 38/37 27/26 29/28 31/30 33/32 35/34 37/36 | |||
|- | |||
!4 | |||
|1003 | |||
|16/9 9/5 34/19 66/37 | |||
|- | |||
!3 | |||
|752 | |||
|48/31 20/13 17/11 31/20 37/24 | |||
|- | |||
!2 | |||
|501 | |||
|4/3 27/20 | |||
|- | |||
!1 | |||
|251 | |||
|36/31 22/19 15/13 38/33 31/27 '''''37/32''''' | |||
|- | |||
!0 | |||
| class="thl" |0 | |||
| class="thl" |'''''1/1''''' | |||
|- | |||
!-1 | |||
|949 | |||
|64/37 26/15 19/11 54/31 31/18 33/19 | |||
|- | |||
!-2 | |||
|699 | |||
|'''''3/2''''' 40/27 | |||
|- | |||
!-3 | |||
|448 | |||
|48/37 40/31 22/17 13/10 31/24 | |||
|- | |||
!-4 | |||
|197 | |||
|10/9 9/8 19/17 37/33 | |||
|- | |||
!-5 | |||
|1146 | |||
|64/33 56/29 72/37 52/27 60/31 68/35 25/13 '''''31/16''''' 33/17 37/19 | |||
|- | |||
!-6 | |||
|896 | |||
|32/19 5/3 52/31 27/16 62/37 37/22 | |||
|- | |||
!-7 | |||
|645 | |||
|16/11 13/9 42/29 54/37 | |||
|- | |||
!-8 | |||
|394 | |||
|24/19 '''''5/4''''' 44/35 29/23 | |||
|- | |||
!-9 | |||
|143 | |||
|12/11 40/37 13/12 38/35 37/34 | |||
|- | |||
!-10 | |||
|1093 | |||
|32/17 36/19 15/8 50/27 62/33 66/35 | |||
|- | |||
!-11 | |||
|842 | |||
|18/11 '''''13/8''''' 60/37 34/21 50/31 31/19 | |||
|- | |||
!-12 | |||
|591 | |||
|24/17 52/37 25/18 27/19 31/22 | |||
|- | |||
!-13 | |||
|340 | |||
|40/33 28/23 17/14 27/22 35/29 | |||
|- | |||
!-14 | |||
|90 | |||
|20/19 18/17 22/21 25/24 37/35 | |||
|- | |||
!-15 | |||
|1039 | |||
|64/35 20/11 38/21 42/23 46/25 31/17 | |||
|- | |||
!-16 | |||
|788 | |||
|11/7 52/33 30/19 25/16 27/17 | |||
|- | |||
!-17 | |||
|537 | |||
|48/35 26/19 15/11 19/14 50/37 | |||
|- | |||
!-18 | |||
|287 | |||
|20/17 13/11 34/29 33/28 | |||
|- | |||
!-19 | |||
|36 | |||
|36/35 | |||
|- | |||
!-20 | |||
|985 | |||
|30/17 23/13 62/35 37/21 | |||
|- | |||
!-21 | |||
|734 | |||
|32/21 44/29 26/17 23/15 50/33 54/35 35/23 | |||
|- | |||
!-22 | |||
|484 | |||
|38/29 25/19 37/28 | |||
|- | |||
!-23 | |||
|233 | |||
|8/7 23/20 25/22 29/25 33/29 | |||
|- | |||
!-24 | |||
|1182 | |||
| | |||
|- | |||
!-25 | |||
|931 | |||
|12/7 46/27 | |||
|- | |||
!-26 | |||
|681 | |||
|52/35 34/23 46/31 25/17 31/21 | |||
|- | |||
!-27 | |||
|430 | |||
|9/7 23/18 37/29 | |||
|- | |||
!-28 | |||
|179 | |||
|32/29 28/25 29/26 31/28 | |||
|- | |||
!-29 | |||
|1128 | |||
|40/21 44/23 23/12 27/14 29/15 | |||
|- | |||
!-30 | |||
|878 | |||
|48/29 38/23 42/25 | |||
|- | |||
!-31 | |||
|627 | |||
|10/7 '''''23/16''''' 29/20 33/23 | |||
|- | |||
!-32 | |||
|376 | |||
|36/29 26/21 46/37 | |||
|- | |||
!-33 | |||
|125 | |||
|14/13 15/14 29/27 31/29 | |||
|} | |||
Like other | == Rank-3 == | ||
Like other well-documented temperaments by [[User:Ground]], it may be understood as a relatively low-complexity rank-3 for greater flexibility. 81/80 is an obvious comma to temper out as seen in the standard rank-2 version, but leaving it in creates a significant amount of generator complexity. With this in mind, rank-3 Intergan is constructed as 2.3.5.11.13.17.19.31.37 5&9&24 with the following comma list: | |||
* 4/3 / (15/13)^2 = 676/675 | * 4/3 / (15/13)^2 = 676/675 | ||
* 22/19 / (15/13) = 286/285 | * 22/19 / (15/13) = 286/285 | ||
| Line 16: | Line 294: | ||
{| class="wikitable" | {| class="wikitable" | ||
|+Rank-3 Intergan, 2.3.5.11.13.17.19.31.37 5&9&24 CE tuning; defining primes highlighted, along with the two most likely mappings of 7, 23, and 29 | |+Rank-3 Intergan, 2.3.5.11.13.17.19.31.37 5&9&24 CE tuning; defining primes highlighted, along with the two most likely mappings of 7, 23, and 29 | ||
! | |||
! -5 | |||
! -4 | |||
! -3 | |||
! -2 | |||
! -1 | |||
!0 | |||
!1 | |||
!2 | |||
!3 | |||
!4 | |||
!5 | |||
|- | |- | ||
! -5 | |||
|482 | |482 | ||
|877 | |877 | ||
| Line 42: | Line 320: | ||
|827 | |827 | ||
|- | |- | ||
! -4 | |||
|231 | |231 | ||
| class="thl" |'''626''' | | class="thl" |'''626''' | ||
| Line 55: | Line 333: | ||
|576 | |576 | ||
|- | |- | ||
! -3 | |||
|1180 | |1180 | ||
|375 | |375 | ||
| Line 68: | Line 346: | ||
|325 | |325 | ||
|- | |- | ||
! -2 | |||
|929 | |929 | ||
|124 | |124 | ||
| Line 81: | Line 359: | ||
|75 | |75 | ||
|- | |- | ||
! -1 | |||
|678 | |678 | ||
|1073 | |1073 | ||
| Line 94: | Line 372: | ||
| class="thl" |'''1024''' | | class="thl" |'''1024''' | ||
|- | |- | ||
!0 | |||
|427 | |427 | ||
|822 | |822 | ||
| Line 107: | Line 385: | ||
|773 | |773 | ||
|- | |- | ||
!1 | |||
|176 | |176 | ||
|571 | |571 | ||
| Line 120: | Line 398: | ||
|522 | |522 | ||
|- | |- | ||
!2 | |||
|1125 | |1125 | ||
|320 | |320 | ||
| Line 133: | Line 411: | ||
|271 | |271 | ||
|- | |- | ||
!3 | |||
|875 | |875 | ||
|69 | |69 | ||
| Line 146: | Line 424: | ||
|20 | |20 | ||
|- | |- | ||
!4 | |||
|624 | |624 | ||
|1018 | |1018 | ||
| Line 159: | Line 437: | ||
|969 | |969 | ||
|- | |- | ||
!5 | |||
|373 | |373 | ||
|767 | |767 | ||
| Line 173: | Line 451: | ||
|} | |} | ||
Being so close to 24edo means that 1/2, 1/3, 1/4, 1/6, and 1/8-octave temperaments are all available. 12edo's remarkable accuracy in 2.3.17.19 provides many ways to temper the subgroup and its extensions, but this requires more effort to produce a temperament that isn't virtually 12edo; Intergan's interseptimals are one option. The rank-3 temperament may be attached to one of numerous often multi-period temperaments in this subgroup to reduce it to rank-2. | Being so close to 24edo means that 1/2, 1/3, 1/4, 1/6, and 1/8-octave temperaments are all available. 12edo's remarkable accuracy in 2.3.17.19 provides many ways to temper the subgroup and its extensions, but this requires more effort to produce a temperament that isn't virtually 12edo; Intergan's interseptimals are one option. The rank-3 temperament may be attached to one of numerous often multi-period temperaments in this subgroup to reduce it to rank-2. | ||
* Third-octave: 121172^-11 = 2057/2048 | * Third-octave: Add 121172^-11 = 2057/2048, called the Blume comma, and it is obscure despite being both accurate and low-complexity. The third-octave version of Intergan is especially useful when adding the elusive prime 29 because 29/23 is 401¢. It is equivalent to adding the 2/(5/4)^3 = 128/125 Augmented comma. (27/17)^3/4 = 19683/19652 is a typical comma for third-octave temperaments but it has significantly more complex result. | ||
* Quarter-octave: | * Quarter-octave: Add the (6/5)^4/2 = 648/625 Diminished comma or the smaller 2/(19/16)^4 = 131072/130321. These are the two most useful commas dividing the octave into four equal parts besides the (25/21)^4/2 = 390625/388962 Dimcomp comma. | ||
The different versions of Intergan may be defined by the sheer number of intervals it maps to | 2.3.5.11.13.17.19.31.37 edos: | ||
* Meantone: 24, 19, 43, 5, 67, 110[+5, +19], 91[+5], 115[+5] | |||
* Augmented: 24, 9, 15, 33[+31], 57[+5, +31] | |||
* Diminished: 24, 52, 76[+5] | |||
The different versions of Intergan may be defined by the sheer number of intervals it maps to ~19/16: 19/16, 25/21, 31/26, 32/27, 37/31, 44/37. The semiquartal temperament equates all of them besides 25/21 due to its sharp 5, instead equating it to 6/5 in the 7-limit. This includes an accurate otonal approximation of 0-1-2-3\4, 26:31:37:44. | |||
{{Navbox regtemp}} | {{Navbox regtemp}} | ||
{{Cat|temperaments}} | {{Cat|temperaments}} | ||
Latest revision as of 05:22, 12 July 2026
Intergan is a set of temperaments related to 24edo semiquartal. The term is short for "interseptimal Ganassi," after 12edo's 2.3.17.19 Ganassi temperament. It seeks to cover all of the notable concordances generated by a meantone-range semifourth. It was specified in a 2023 Tumblr post.
Semiquartal
- The most basic version is 2.3.11.13/5.17.19 5&24. 4/3 is split into two semifourths most simply represented by 15/13, and 22/17 is equated to 13/10 and 22/19 is equated to 15/13. It features the remarkably simple 10:13:15 ultramajor triad and its retroversion found in Island temperaments, along with the 16:19:22 +1+1 sub-diminished triad and 16:19:24:27 +3+5+3 minor add6 tetrad. 11:12:17:19 is present, although this adding 13, 14, or 15 to the subgroup will significantly improve its usefulness.
- Tempering out 81/80 is somewhat obvious, resulting in 2.3.5.11.13.17.19 5&24.
- Primes 31 and 37 are also obvious to add, equating 37/32 to 22/19 and 37/31 to 19/16, resulting in 2.3.5.11.13.17.19.31.37 5&24. 67edo is roughly optimal due to its very mild meantone fourth being split in half. The 2.31.37 restriction is highly accurate in 43edo.
- Primes 7, 23, and 29 are all more difficult to map due to their complexity, although their difficulty is in ascending order. They are more easily reached by splitting the semifourth generator in half in a manner similar to Negri.
| Gens | Cents | JI Interpretations |
|---|---|---|
| 33 | 1075 | 28/15 13/7 54/29 58/31 |
| 32 | 824 | 21/13 29/18 37/23 |
| 31 | 573 | 32/23 40/29 7/5 46/33 |
| 30 | 322 | 23/19 25/21 29/24 |
| 29 | 72 | 24/23 28/27 30/29 21/20 23/22 |
| 28 | 1021 | 56/31 52/29 25/14 29/16 |
| 27 | 770 | 14/9 36/23 58/37 |
| 26 | 519 | 34/25 42/31 23/17 31/23 35/26 |
| 25 | 269 | 7/6 27/23 |
| 24 | 18 | |
| 23 | 967 | 40/23 7/4 44/25 50/29 58/33 |
| 22 | 716 | 56/37 38/25 29/19 |
| 21 | 466 | 30/23 17/13 21/16 46/35 29/22 33/25 35/27 |
| 20 | 215 | 26/23 17/15 42/37 35/31 |
| 19 | 1164 | 35/18 |
| 18 | 913 | 56/33 22/13 17/10 29/17 |
| 17 | 663 | 28/19 22/15 19/13 35/24 37/25 |
| 16 | 412 | 32/25 14/11 34/27 19/15 33/26 |
| 15 | 161 | 11/10 34/31 21/19 23/21 25/23 35/32 |
| 14 | 1110 | 48/25 17/9 19/10 21/11 70/37 |
| 13 | 860 | 28/17 44/27 23/14 58/35 33/20 |
| 12 | 609 | 36/25 44/31 17/12 38/27 37/26 |
| 11 | 358 | 16/13 11/9 38/31 21/17 31/25 37/30 |
| 10 | 107 | 16/15 17/16 19/18 27/25 33/31 35/33 |
| 9 | 1057 | 24/13 11/6 68/37 35/19 37/20 |
| 8 | 806 | 8/5 19/12 46/29 35/22 |
| 7 | 555 | 18/13 11/8 29/21 37/27 |
| 6 | 304 | 32/27 6/5 44/37 19/16 31/26 37/31 |
| 5 | 54 | 32/31 26/25 34/33 38/37 27/26 29/28 31/30 33/32 35/34 37/36 |
| 4 | 1003 | 16/9 9/5 34/19 66/37 |
| 3 | 752 | 48/31 20/13 17/11 31/20 37/24 |
| 2 | 501 | 4/3 27/20 |
| 1 | 251 | 36/31 22/19 15/13 38/33 31/27 37/32 |
| 0 | 0 | 1/1 |
| -1 | 949 | 64/37 26/15 19/11 54/31 31/18 33/19 |
| -2 | 699 | 3/2 40/27 |
| -3 | 448 | 48/37 40/31 22/17 13/10 31/24 |
| -4 | 197 | 10/9 9/8 19/17 37/33 |
| -5 | 1146 | 64/33 56/29 72/37 52/27 60/31 68/35 25/13 31/16 33/17 37/19 |
| -6 | 896 | 32/19 5/3 52/31 27/16 62/37 37/22 |
| -7 | 645 | 16/11 13/9 42/29 54/37 |
| -8 | 394 | 24/19 5/4 44/35 29/23 |
| -9 | 143 | 12/11 40/37 13/12 38/35 37/34 |
| -10 | 1093 | 32/17 36/19 15/8 50/27 62/33 66/35 |
| -11 | 842 | 18/11 13/8 60/37 34/21 50/31 31/19 |
| -12 | 591 | 24/17 52/37 25/18 27/19 31/22 |
| -13 | 340 | 40/33 28/23 17/14 27/22 35/29 |
| -14 | 90 | 20/19 18/17 22/21 25/24 37/35 |
| -15 | 1039 | 64/35 20/11 38/21 42/23 46/25 31/17 |
| -16 | 788 | 11/7 52/33 30/19 25/16 27/17 |
| -17 | 537 | 48/35 26/19 15/11 19/14 50/37 |
| -18 | 287 | 20/17 13/11 34/29 33/28 |
| -19 | 36 | 36/35 |
| -20 | 985 | 30/17 23/13 62/35 37/21 |
| -21 | 734 | 32/21 44/29 26/17 23/15 50/33 54/35 35/23 |
| -22 | 484 | 38/29 25/19 37/28 |
| -23 | 233 | 8/7 23/20 25/22 29/25 33/29 |
| -24 | 1182 | |
| -25 | 931 | 12/7 46/27 |
| -26 | 681 | 52/35 34/23 46/31 25/17 31/21 |
| -27 | 430 | 9/7 23/18 37/29 |
| -28 | 179 | 32/29 28/25 29/26 31/28 |
| -29 | 1128 | 40/21 44/23 23/12 27/14 29/15 |
| -30 | 878 | 48/29 38/23 42/25 |
| -31 | 627 | 10/7 23/16 29/20 33/23 |
| -32 | 376 | 36/29 26/21 46/37 |
| -33 | 125 | 14/13 15/14 29/27 31/29 |
Rank-3
Like other well-documented temperaments by User:Ground, it may be understood as a relatively low-complexity rank-3 for greater flexibility. 81/80 is an obvious comma to temper out as seen in the standard rank-2 version, but leaving it in creates a significant amount of generator complexity. With this in mind, rank-3 Intergan is constructed as 2.3.5.11.13.17.19.31.37 5&9&24 with the following comma list:
- 4/3 / (15/13)^2 = 676/675
- 22/19 / (15/13) = 286/285
- 13/10 / (22/17) = 221/220
- 16/15 / (17/16) = 256/255
- 37/32 / (15/13) = 481/480
- 37/31 / (19/16) = 592/589
It seems obvious to add (22/17)^2/(5/3) = 1452/1445, but that's equivalent to adding 81/80, as is 5/4/(19/17)^2 = 1445/1444.
| -5 | -4 | -3 | -2 | -1 | 0 | 1 | 2 | 3 | 4 | 5 | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| -5 | 482 | 877 | 71 | 466 | 860 | 55 | 449 | 844 | 38 | 433 | 827 |
| -4 | 231 | 626 | 1020 | 215 | 609 | 1004 | 198 | 593 | 987 | 182 | 576 |
| -3 | 1180 | 375 | 769 | 1164 | 358 | 753 | 1147 | 342 | 736 | 1131 | 325 |
| -2 | 929 | 124 | 518 | 913 | 107 | 502 | 896 | 91 | 485 | 880 | 75 |
| -1 | 678 | 1073 | 267 | 662 | 1056 | 251 | 645 | 1040 | 235 | 629 | 1024 |
| 0 | 427 | 822 | 16 | 411 | 805 | 0 | 395 | 789 | 1184 | 378 | 773 |
| 1 | 176 | 571 | 965 | 160 | 555 | 949 | 144 | 538 | 933 | 127 | 522 |
| 2 | 1125 | 320 | 715 | 1109 | 304 | 698 | 1093 | 287 | 682 | 1076 | 271 |
| 3 | 875 | 69 | 464 | 858 | 53 | 447 | 842 | 36 | 431 | 825 | 20 |
| 4 | 624 | 1018 | 213 | 607 | 1002 | 196 | 591 | 985 | 180 | 574 | 969 |
| 5 | 373 | 767 | 1162 | 356 | 751 | 1145 | 340 | 734 | 1129 | 323 | 718 |
Being so close to 24edo means that 1/2, 1/3, 1/4, 1/6, and 1/8-octave temperaments are all available. 12edo's remarkable accuracy in 2.3.17.19 provides many ways to temper the subgroup and its extensions, but this requires more effort to produce a temperament that isn't virtually 12edo; Intergan's interseptimals are one option. The rank-3 temperament may be attached to one of numerous often multi-period temperaments in this subgroup to reduce it to rank-2.
- Third-octave: Add 121172^-11 = 2057/2048, called the Blume comma, and it is obscure despite being both accurate and low-complexity. The third-octave version of Intergan is especially useful when adding the elusive prime 29 because 29/23 is 401¢. It is equivalent to adding the 2/(5/4)^3 = 128/125 Augmented comma. (27/17)^3/4 = 19683/19652 is a typical comma for third-octave temperaments but it has significantly more complex result.
- Quarter-octave: Add the (6/5)^4/2 = 648/625 Diminished comma or the smaller 2/(19/16)^4 = 131072/130321. These are the two most useful commas dividing the octave into four equal parts besides the (25/21)^4/2 = 390625/388962 Dimcomp comma.
2.3.5.11.13.17.19.31.37 edos:
- Meantone: 24, 19, 43, 5, 67, 110[+5, +19], 91[+5], 115[+5]
- Augmented: 24, 9, 15, 33[+31], 57[+5, +31]
- Diminished: 24, 52, 76[+5]
The different versions of Intergan may be defined by the sheer number of intervals it maps to ~19/16: 19/16, 25/21, 31/26, 32/27, 37/31, 44/37. The semiquartal temperament equates all of them besides 25/21 due to its sharp 5, instead equating it to 6/5 in the 7-limit. This includes an accurate otonal approximation of 0-1-2-3\4, 26:31:37:44.
