| Interesting thread, Fred. When I first studied tritone substitution my teacher kept pounding at me that "thirds become sevenths and sevenths become thirds". One day the light went on and I understood. Invented by Paganini BTW, Contemporaries envious of his skills called it "the Devil's interval".
I use the "triad above the dom 7th all the time; it's great inverted, played down to the seventh of the dominant and up a whole tone for a finish.
If you want to hear some really great use of extended chords, tritone substitutions and polytones, in addition to Bird take a listen to anything Buddy DeFranco recorded in the last 30 years. He's really way out there!
I'm tuned in well enough to hear the tritones and his use of extended chords but I've never figured out what polytones are. He certainly does not give voice to 2 notes at the same time so that's not it.
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Tom// |