Pseudo-semaphore

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Pseudo-semaphore is a weird temperament in which the third harmonic does not have a single consistent mapping. If you want to force it into the regular mapping paradigm you have to think of it as a 2.3.3'.7 temperament.

It's called "pseudo-semaphore" because it has the same MOS structure as semaphore, but 49/48 is not tempered out. Perhaps it's better to think of it as superpyth in which the 4/3 generator has been split in half forming a weird interval that's neither 8/7 nor 7/6.

Interval chain

204. 448. 692. 936. 1180. 224. 468. 712. 956. 0. 244. 488. 732. 976. 20. 264. 508. 752. 996.
9/8 9/7 3/2 (flat) 12/7 9/8~8/7 3/2 (sharp) 1/1 4/3 (flat) 7/4~16/9 7/6 4/3 (sharp) 14/9 16/9

MOSes

5-note (LLLLs, proper)

The 5-note MOS is not much use because only one of the two different mappings shows up. You'd be better off using semaphore[5] or superpyth[5] (or 5edo).

Small ("minor") interval 224. 468. 712. 956.
JI intervals represented 9/8~8/7 3/2
Large ("major") interval 244. 488. 732. 976.
JI intervals represented 4/3 7/4~16/9

9-note (LLsLsLsLs, improper)

Here's where all the action begins. Note that this nine-note scale contains nine 4/3s and nine 3/2s. The only way this is possible with a single mapping for 3 is an equal temperament, and all of these 4/3s and 3/2s are much more accurate than in 9edo.

Small ("minor") interval 20. 244. 264. 488. 508. 732. 752. 976.
JI intervals represented 7/6 4/3 (flat) 4/3 (sharp) 14/9 7/4~16/9
Large ("major") interval 224. 448. 468. 692. 712. 936. 956. 1180.
JI intervals represented 9/8~8/7 9/7 3/2 (flat) 3/2 (sharp) 12/7