Originally Posted by
morpeth
Hi Lawrence.
I can help you with this specific example: So What is a modal composition (as are most of the pieces on Kind of Blue), which means that the improvising happens over specific pre-determined scales rather than changing chords.
In this case, the structure is a 32 bar AABA form: 8 bars of D minor dorian, 8 bars of D minor dorian, 8 bars of Eb minor dorian, 8 bars of D minor dorian. Dorian mode uses the second note of a major scale as its tonic, so D minor dorian uses all the notes of C major, Eb dorian uses the notes of Db major.
If you listen closely to what Paul Chambers plays on the bass, you'll hear that he stays fairly closely within each scale in the relevant sections, but the static nature of the harmony - 16 bars D minor, then a shift up a semitone - means he has freedom to wander around quite a lot within the scale.
Not the clearest explanation, but I hope it's some use.