Diaschismic straddle temperaments

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Diaschismic tempers out 2048/2025 = 2/((9/8)(5/4))^2. Normally the subgroup is interpreted as 2.3.5, but 2.9.5 is also possible. This provides a great opportunity for straddling 3, where flat 3 (3/a in SRTT) and sharp 3 (3a) cancel out to make 9.

Of the Diaschismic extensions to the 7-limit, Septimal Diaschismic tempers out 126/125, another 2.9.5.7 comma, and Pajara uses the sharp 3, tempering out 64/(3a*7) = 64/63 a^-1. These are equivalent.

Diaschismic Porcupine

Diaschismic Porcupine tempers out 2048/2025 and 250/243 a^-5, the Porcupine comma with 3 replaced with 3a, as 3 is usually tuned quite sharp. Without straddling 3, only 22edo tempers out 2048/2025 and 250/243 in 2.3.5.

Porcupine mappings extend to the 11-limit and the Diaschismic mapping adds prime 17, implying that 17 is straddled like 3. 13 may be added using the Oceanfront mapping of 81/64 a^4 = 13/10.

One possible GTO string resembling the 74edo tuning is 600 | 2.<3.>>3.>5.>7.11.<17.>>17 || 0 8 -3 -5 6 -4 8 -3. This focuses on approximating 9/5, 9/7, 17/5, 17/7, and 11/9 about equally well, with >17/14 equated to <11/9.

Diaschismic Semioceanfront

Diaschismic Semioceanfront has a generator of half of an Oceanfront fourth rather than a third. The generator is also equivalent to 13/8 due to the half-octave period.