Planar temperaments -- 64/63

The tunings I have been getting with planar temperaments have been so
good I thought I'd try a larger comma. This is one of the classics,
with some tone relationships familiar from the 12-et. We have
7/4 ~ (4/3)^2, and we can use 2,3/2 and 5/4 as generators; meaning we
have the familiar 5-limit lattice, with some 7 approximations added.

The 7-limit least squares gives us a fifth 9.74 cents sharp, a major
third 5.84 cents sharp, and a 7 7.79 cents sharp. It is instructive
to compare this to the 22 and 27 ets, where we have 7.14, -4.5, 12.99
for the 22-et and 9.16, 13.69, and 8.95 for the 27-et; the tuning of
the planar temperament is a significant improvement.

We have

7/5 -- 6/5 -- 8/5 -- 16/15 -- 9/5
| | | | |
7/4 -- 4/3 -- 1 -- 3/2 -- 9/8
| | | | |
10/9-- 5/3 -- 5/4 -- 15/8 --10/7