166

A division which has received zero attention, so far as I know, is 166,
but it's actually quite interesting from one point of view, which is
that of extending marvel (225/224-planar) temperament to higher limits.

The best way to extend marvel to an 11-limit version seems to be to add
385/384 to the mix, so that 225/224, 385/384, and 540/539 are all
tempered out. 166 is excellent for this, but it also tempers out
325/324, which may be added to produce what looks to me to be the best
version of 13-limit marvel. This is an addition of succesive bridge
commas, and so we may express everything in 13-limit marvel in terms of
5-limit intervals, and then temper by 166-et to get the marvel
tempering. The 5-limit approximations then are

7 ~ 225/32
11 ~ 4096/375
13 ~ 324/25

All of these, of course, are exact equivalences in 166.