ExampleS permutations of four-note units

This line stays slavishly within CAGED shape #2 from Diagram 1. It changes from major to minor at least six times. Can you see where? As usual, your clue is a C note (minor 3rd) for minor and C# (major 3rd) for major (dominant).

The next three lines dwell within CAGED shaped #3. Although the Eb

at the end of the first beat in bar 13 could be seen as coming from A minor Blues scale, it really just forms a chromatic bridging device between D and E (in a chromatic ascent that actually starts from C#); so, this bar should be seen as being derived ostensibly from A Mixolydian. Bar 14 sees the minor 3rd

EE(C) introduced twice; first, on its way to resolving to the major 3rd (C#) and, secondly, as a means of ending the entire line on a sour note.

The bulk of this shape #3 line uses the A minor Blues scale. It’s only in the last five notes that it switches to A major Pentatonic scale (as usual, starting with the C# note – the fundamental difference between minor and dominant/major tonality).

Apart from the first note of beat 2 (bar 21), this final shape #3 line is entirely minor (mainly A Dorian blues: 1-2- 4- 5-6-