back to list

Some 7-limit 13-note no-fives Fokker blocks

🔗Gene Ward Smith <gwsmith@svpal.org>

10/1/2005 9:59:37 PM

Inspired, if that is the word, by the 14-note blocks with
2048/2025 and 2048/1875 as boundries, which worked out nicely for
marvel tempering, I decided to investigate 16807/12800 and
117649/100000, which gives 13-note Fokker blocks long in the
3*(2401/2400) direction, and therefore which might be good candidates
for breed tempering. As expected, I obtained 13 of these; the one
below has three otonal and two utonal tetrads upon breed tempering. In
the breed plane, the scale is far from bizarre looking; with 10/7
along the horizonal axis and 49/40 along the veritical axis, we get a
4x4 square of notes, with two removed from the upper right-hand corner
and one from the lower left-hand corner. "Triskabree", incidentally,
is contracted from triskaideca-breed. Here it is, in all it's
irregular, non-epimorphic glory:

! triskabree12.scl
Twelvth 16807/12800&117649/100000 scale = inverse triskabree13
13
!
28/25
8/7
2401/2000
64/49
3200/2401
343/250
7/5
8/5
80/49
16807/10000
640/343
49/25
2