fingerboard for blues in A

I wanted to be able to play a I-IV-V progression of full harmonic seventh chords (4:5:6:7). I chose the key of A. The three chords give a 10-tone scale that includes two different D's: 4/3 and 21/16, so it's really more of a 9-tone scale where one tone has two versions:
1/1 9/8 7/6 5/4 21/16 4/3 3/2 5/3 7/4 15/8
I wanted to fill out a 12-tone scale, so chose a septimal minor sixth, and two more to give most of a 5-limit C minor scale, resulting in:
1/1 21/20 9/8 7/6 5/4 21/16 4/3 7/5 3/2 14/9 5/3 7/4 15/8
See also the harmonic melodic diagram below.

Note: I let the 3/2 fret and the 2/1 fret continue straight across both for simplicity and as convenient landmarks.

Harmonic Melodic Diagram

The graphics on this page are bitmapped versions of the EPS files blue_f.eps (frets) and blue_h.eps (diagram).

last updated 1999 Oct 10

David Canright -- DCanright@NPS.edu