THE Blackjack guitar

Ok. I think this is it. I think this is _the_ Blackjack open string tuning.
Sorry about all that earlier waffle.

Legend for 72-tET notation:

A,B,C,D,E,F,G,#,b as for 12-tET
] = quarter-tone up (+50 c)
> = sixth-tone up (+33 c)
^ = twelfth-tone up (+17 c)
v = twelfth-tone down (-17 c)
< = sixth-tone down (-33 c)
[ = quarter-tone down (-50 c)

E[ 350c G 350c B[ 383c D> 350c Fv 350c A>
|--9:11-|--9:11-|--4:5--|--9:11-|--9:11-|
|------2:3------| |------2:3------|
|----------8:15---------|
|----------8:15---------|
|----------8:15---------|

The point of symmetry of the blackjack scale (i.e. the middle fret of the
only set of 3 close-together frets) must be positioned a perfect fourth
from the nut. i.e it is the 9th fret.

It spans 7 generators. It has no gaps in the Blackjack home key.

The thing about it that took me the longest time to accept was that it
spans only 1783 cents between outside strings; well short of the usual 2400
cents. But everything else about it just works so well! (on paper at least)

A JI C-major and E-minor scale are quite playable between the 6th and 12th
frets and all the 5-limit triads are laid out beautifully there.

So many 5, 7, 9 and 11-limit stack-of-thirds type chords should fall
beautifully under the fingers simply because all the intervals between
strings are close to a neutral third, so you don't have to move far to turn
them into anything from a subminor third 6:7, thru to a supermajor third 7:9.

Regards,
-- Dave Keenan
-- Dave Keenan
Brisbane, Australia
http://dkeenan.com