A backing track for lead instrumentalists to improvise over.  
Chords used are:
section 1: Cmaj7, Dm7, Em7, Dm7
section 2: Fmaj9, G7sus4, Am7, G7sus4
link after section 2: Bm7b5
Scales to explore are:
C major (C Ionian), D Dorian, E Phrygian, F Lydian, G Mixolydian, A Aeolian (A natural minor), B Locrian - i.e. all the modes of C major.
Also try the A minor pentatonic, D minor pentatonic, and E minor pentatonic, as these are all subsets of the notes belonging to C major.


Backing track #1: C major

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