Mintaka

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Mintaka is a temperament in the 3.7.11 subgroup where ~11/7 is a generator, and the comma 1331/1323 is tempered out, so a stack of two generators represents 27/11 in addition to 121/49, and a stack of three generators, tritave-reduced, represents 9/7. As 11/7 as a generator against the tritave produces a 5L 2s (macrodiatonic) scale, with the generator here occupying the role of a perfect fourth, it is possible to use an analogue of the chain-of-fifths notation that is standardly used for diatonic scales, with the understanding that sharps are sharper than flats (for example, A♯ is sharper than B♭) and that all intervals are extremely stretched, though the 5L 7s macrochromatic scale is suggested for musical use due to the hardness of the macrodiatonic and the increased breadth of the tritave. 9\22edt is a very good tuning for the generator, and 22edt overall excels in the 3.7.11 subgroup, but other tunings such as 7\17edt and 16\39edt are also useful.

As perhaps the simplest temperament of this subgroup delivering decent accuracy - and, in particular, the simplest supported by tunings such as 17edt and 22edt - Mintaka can be considered the 3.7.11 analog of 3.5.7 BPS or 2.3.5 meantone, using 7:9:11 as its fundamental consonant chord in the place of 3:5:7 or of 4:5:6.

Mos scales of reasonable tunings have cardinalities of 5 (2L 3s), 7 (5L 2s), 12 (5L 7s), or 17 (5L 12s).

For technical data, see No-twos subgroup temperaments#Mintaka.

Extensions of Mintaka

Several extensions of this temperament are possible to incorporate additional harmonics.

Add 20 and 23/4

Off the bat, given that 1331/1323 is a lopsided comma with S-expression S222 * S23, one can reliably choose to temper both S22 = 484/483 and S23 = 529/528 in the 3.7.11.23/4 subgroup, which equates the 11/7 generator to 36/23, and the interval 11/9 to 28/23. Furthermore, the tiny comma S161 = 25921/25920 can be tempered to add harmonic 20 to the subgroup, finding it 8 generators down. More neatly, this can be expressed as the temperament that tempers out the commas 253/252, 484/483, and 540/539 in the 3.7.11.20.23/4 subgroup.

Add 13 and 19

There are two reasonable ways to incorporate prime 13 into the subgroup. For tunings of the generator sharper than 9\22edt, the step 81/77 approaches or exceeds 260/243 in quality, and therefore can be identified with 260/243 by tempering out 20020/19683, equating 27/13 to (77/81)(20/9), 13 generators down (or alternatively, if one refuses to admit the even number 20 into the subgroup, by tempering out 218491/216513). The alternative extension to include prime 13, known as Minalzidar, works better for tunings flatter than 9\22edt, where it is the most accurate to find 13/9 at 3(9/7)-3, 9 generators up, tempering out the comma 351/343. The two representations meet at 22edt.

Once either representation of prime 13 is added to the system, it is reasonable to temper out 247/243, which equates 19/9 to 27/13.

Add 4 and 5

For tunings of the generator that possess a sharp 9/7 (sharper than 1/3 comma), it is reasonable to combine this temperament with BPS (as well as Deneb in the 3.5.11 subgroup), and additionally temper out 245/243, thereby equating 5/3 to 81/49 at 6 generators up. This is Mintra temperament, which splits the BPS generator in three. In this range, the "canonical" extension to primes 13 and 19 makes sense, though it is worth noting that the Minalzidar extension corresponds directly to the 3.5.7.13.19 extension of BPS. With the inclusion of 20 in the subgroup above, 4/3 would therefore also appear, at the position of (20/9)/(5/3), 14 generators down.

If we combine all of the above, using the sharper representation of 5, 13, and 19, we find the complete 3.4.5.7.11.13.19.23 temperament with commas 100/99, 133/132, 247/245, 253/252, 484/483, and 540/539.

Eshurizel

In the flatter generator range (supported by the Minalzidar extension), the optimal representation of 5 is instead that obtained by tempering out 120285/117649, which equates 5 with (529/243)2, placing it 16 generators down. However, as soon as harmonic 20 is inserted, this also equates 5 with (20/9)2, tempering 81/80 in the 3.4.5 subgroup. Furthermore, this then equates 4/3 to 27/20, 8 generators up, therefore creating a square root of 4 at 4 generators up and making this an insane restriction of meantone that must be fixed by including a mapping for 2, which turns out to equate it to the false octave of 243/121 or 99/49. Therefore, as soon as prime 5 is incorporated, this temperament folds into Eshurizel, an elaborate add-19 add-23 extension of 11-limit squares (with commas 81/80, 99/98, and 243/242).

Even without the mappings for other primes, this method can be used to introduce octaves into Mintaka in a manner alike to sensi and hedgehog being produced as extensions of BPS. Equating the false octave (243/121~99/49) to 2/1 provides 2.3.7.11 skwares temperament, to which the aforementioned Eshurizel is but an extension.

Interval chains

One important feature of subgroups involving 3 and 11 is the quasi-octave at the interval designated 243/121; in this temperament, it is equated to 99/49 and placed four generators up. In flatter tunings of the generator, this is closer to a true octave. This interval is meriting of special treatment in terms of consonance and dissonance.

Tritave-reduced harmonics below 243 are marked in bold.

Basic temperament
# Cents* Approximate Ratios
3.7.11 subgroup 3.7.11.20.23/4 extension
-4 690.0 49/33, 121/81 161/108, 180/121
-3 1468.5 7/3 180/77
-2 345.0 11/9, 147/121 28/23, 60/49
-1 1123.5 21/11, 121/63 23/12, 44/23
0 0.0 1/1 253/252, 484/483, 540/539
1 778.5 11/7, 189/121 36/23, 69/44
2 1556.9 27/11, 121/49 69/28, 49/20
3 433.4 9/7 77/60
4 1211.9 99/49, 243/121 324/161, 121/60
5 88.4 81/77, 363/343 207/196, 21/20
6 866.9 81/49 33/20
7 1645.4 891/343, 2187/847 207/80
8 521.9 729/539 759/560, 27/20
*  In 3.7.11-targeted DKW tuning

Mintra

Good tunings of Mintra lie on the sharper side of the generator range, and include 17edt, 39edt, 56edt, and 61edt. However, none of these save 61edt support every extension without warts.

Mintra
# Cents* Approximate Ratios
3.5.7.11 subgroup 3.5.7.11.13.19 extension Add-4 add-23 extension
-4 680.9 81/55, 49/33, 121/81 95/63, 135/91, 175/117, 247/165, 513/343 28/19, 52/35, 77/52, 115/77, 147/100, 180/121, 207/140
-3 1461.7 7/3, 81/35 247/105, 275/117, 285/121 44/19, 121/52, 180/77, 231/100, 513/220
-2 340.5 11/9, 147/121, 297/245 95/77, 175/143, 741/605 23/19, 28/23, 60/49, 63/52, 91/75, 121/100, 133/108, 171/140
-1 1121.2 21/11, 121/63 25/13, 95/49, 475/243 23/12, 36/19, 44/23, 52/27, 143/75, 189/100
0 0.0 1/1, 245/243 247/245, 275/273 100/99, 133/132, 209/207, 253/252, 540/539
1 780.8 11/7, 189/121, 1715/1089 39/25, 147/95, 637/405, 729/475 19/12, 36/23, 39/25, 69/44, 81/52, 100/63
2 1561.5 27/11, 121/49, 245/99 231/95, 429/175, 605/247 49/20, 52/21, 57/23, 69/28, 140/57, 225/91, 300/121, 324/133
3 440.3 9/7, 35/27 121/95, 315/247, 351/275 57/44, 77/60, 100/77, 156/121, 207/161, 220/171
4 1221.1 55/27, 99/49, 243/121 91/45, 189/95, 343/171, 351/175, 495/247 57/28, 100/49, 105/52, 121/60, 140/69, 156/77, 231/115
5 99.9 35/33, 81/77, 363/343, 605/567 99/95, 143/135, 247/231, 539/513 20/19, 21/20, 52/49, 55/52, 171/161
6 880.6 5/3, 81/49 91/55, 247/147, 847/513 33/20, 220/133, 420/253
7 1661.4 55/21, 891/343 49/19, 91/35, 243/95, 637/243 60/23, 95/36, 135/52, 207/80, 363/140
8 540.2 15/11, 605/441, 729/539 77/57, 143/105 27/20, 49/36, 180/133, 260/189
9 1320.9 15/7, 175/81, 729/343 121/57, 441/209, 637/297, 741/343 49/23, 77/36, 297/140
10 199.7 55/49, 135/121, 275/243, 385/343 21/19, 39/35, 91/81, 429/385, 729/665 49/44, 121/108, 161/144, 175/156, 220/161, 243/220
11 980.5 135/77, 175/99, 605/343 33/19, 143/81, 637/363 7/4, 100/57, 243/140, 260/147
12 1761.2 25/9, 135/49 91/33, 363/133, 567/209 11/4, 133/48, 483/176
13 640.0 175/121, 275/189, 495/343 13/9, 27/19, 245/171, 351/245 23/16, 63/44, 100/69, 121/84
*  In 3.5.7.11-subgroup CWE tuning

Tuning spectrum

Edt
Generator
Eigenmonzo
(Unchanged-interval)
Generator
(¢)
Comments
7\17 783.158
11/7 782.492 0-comma
23\56 781.160
39\95 780.803
28/23 780.702
363/343 780.405 1/5-comma
16\39 780.289
57\139 779.938
49/33 779.883 1/4-comma
41\100 779.802
25\61 779.490
59\144 779.273
34\83 779.114
9/7 779.013 1/3-comma
43\105 778.896
52\127 778.753
33/20 778.478
81/77 778.317 2/5-comma
27/20 778.177
778.124 DR 7:9:11, close to 18/43-comma
9\22 778.073
21/20 777.675
11/9 777.274 1/2-comma
38\93 777.143
29\71 776.855
20\49 776.308
31\76 775.797
49/20 775.669
23/12 775.636
11\27 774.871
121/63 772.055 Full comma

Other tunings

  • DKW (3.7.11): ~3 = 1\1, ~11/7 = 778.466

Music

short composition by Wensik in 22edt (without using the temperament's MOS scales), based on the 7:9:11 chord and its inversion, 63:77:99.