Ennealimmal-enneadecal equivalence continuum

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The ennealimmal-enneadecal equivalence continuum is a continuum of 5-limit temperaments which equate a number of ennealimmas ([1 -27 18) with enneadeca comma ([-14 -19 19). This continuum is theoretically interesting in that these are all 5-limit microtemperaments.

All temperaments in the continuum satisfy (2・3-27・518)n ~ (2-14・3-19・519). Varying n results in different temperaments listed in the table below. It converges to ennealimmal as n approaches infinity. If we allow non-integer and infinite n, the continuum describes the set of all 5-limit temperaments supported by 171edo (due to it being the unique equal temperament that tempers both commas and thus tempers all combinations of them). The just value of n is approximately 3.2669545024..., and temperaments having n near this value tend to be the most accurate ones.

Temperaments in the continuum
n Temperament Comma
Ratio Monzo
-4 171 & 2429 [-10 -127 91
-3 171 & 1817 [-11 -100 73
-2 Semidimi [-12 -73 55
-1 Supermajor [-13 -46 37
0 Enneadecal 19073486328125/19042491875328 [-14 -19 19
1 Schismic 32805/32768 [-15 8 1
2 Minortone 50031545098999707/50000000000000000 [-16 35 -17
3 Senior [-17 62 -35
4 171 & 1783 [18 -89 53
5 171 & 2395 [19 -116 71
Ennealimmal 7629394531250/7625597484987 [1 -27 18

Examples of temperaments with fractional values of n:

  • 171 & 3193 (n = -5/2 = -2.5)
  • 171 & 2140 (n = -3/2 = -1.5)
  • 171 & 1087 (n = -1/2 = -0.5)
  • Pnict (n = 1/3 = 0.3)
  • Gammic (n = 1/2 = 0.5)
  • Mutt (n = 2/3 = 0.6)
  • Septichrome (n = 4/3 = 1.3)
  • Geb (n = 3/2 = 1.5)
  • 171 & 1901 (n = 5/2 = 2.5)
  • 171 & 4125 (n = 10/3 = 3.3)
  • 171 & 3125 (n = 7/2 = 3.5)