153edt

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← 152edt153edt154edt →
Prime factorization 32 × 17
Step size 12.4311¢ 
Octave 97\153edt (1205.81¢)
Consistency limit 2
Distinct consistency limit 2
Approximation of prime harmonics in 153edt
Harmonic 2 3 5 7 11 13 17 19 23 29 31
Error Absolute (¢) +5.81 +0.00 -1.75 -0.00 +0.66 -2.63 +5.32 -0.77 +4.11 +0.60 -2.98
Relative (%) +46.8 +0.0 -14.1 -0.0 +5.3 -21.2 +42.8 -6.2 +33.0 +4.8 -24.0
Steps
(reduced)
97
(97)
153
(0)
224
(71)
271
(118)
334
(28)
357
(51)
395
(89)
410
(104)
437
(131)
469
(10)
478
(19)

153edt is notable for being the denominator of a convergent to log3(7/3), after 9edt, 13edt and 35edt, and the last before 3401edt, and therefore has an extremely accurate approximation to 7/3, a mere 0.0036 cents flat. In fact, 153edt demonstrates 11-strong 7-3 telicity, due to the next term in the continued fraction expansion being large (note how much larger 3401 is than 153), although 3401edt in fact surpasses it, demonstrating 16-strong 7-3 telicity.

In the no-twos 7-limit, 153edt supports canopus temperament, which gives it a rather accurate approximation of the 5th harmonic; and it additionally is accurate in the 11-limit, tempering out the comma 387420489/386683451 in the 3.7.11 subgroup. Harmonics 19 and 29 are also notably good.

However, 153edt's approximation of 2/1 is close to maximally bad, meaning that it is as far from an octave-equivalent tuning that an EDT of this size can be (though by this point, it is only 6 or so cents off).