Yes Nigel, 40s & 50s Jump Blues were essential music, and somewhere in there Rock and Roll was born. Some of the other elements were a little harder hit on the 1 & 3 and a simpler, mostly arpeggiated walking bass line with a much bigger thump. And PG, please, please the bass line on a jump blues on the 2-5 turnaround is a chromatic run starting on the 2. It might not be musically correct but anything else sounds wrong.

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