EXPANDED CHORD SCALES:

by Clif Kuplen

The use of the 'bebop scale', specifically the notes C D E F G G# A B as an improvisational tool has led among other things to an expansion into a 'chord scale' by playing every other note. This generates a repeating pattern that alternates between inversions of Cmaj6 and Ddim7.

In looking at the general case of taking any series of 8 objects and selecting four objects from it by taking every other one, it can be seen that only two unique choices exist:

for 1 2 3 4 5 6 7 8 there will exist 1 3 5 7 and 2 4 6 8. If you were to make selections in sequence with each number having a turn at the bottom, you would go through the set twice:

 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 1 3 5 7 2 4 6 8 3 5 7 1 4 6 8 2 5 7 1 3 6 8 2 4 7 1 3 5 8 2 4 6

This is the equivalent of playing a chord scale that goes through the inversions of each of the two chords.

Since this is true no matter what value you assign to the numbers, it can be assumed that any scale created by adding an accidental to a major scale will result in a cycle between two chords.  Since there are five accidentals, this will of course generate five chord scales.  Here they are:

More to come.....

Clif Kuplen