Chet, Mayall was not just a purist Mayall was THE PURIST. He never would have allowed it regardless. Don't rewrite historical fact. There were NO PEDALS it was simply a pair of Genelex Gold Lion KT-66's, which if You can find NOS (not repros) go for anywheres between 400-800 dollars depending on condition. If You put these Valves into a JTM an crank 'em - you're there sonically.