Can someone tell me why the JMP1 that Geoff Whitehorn and many other guitarist used on guitar cds sounds so different from the 4 that I've recorded with? There is a warm fuzzy present quality on these recordings that the JMP1s I've tried don't have. All the ones I've tried sound the same, so I'm sure I don't have a faulty unit. It sounds great though an amp and cab. I've changed the tubes a few times, but it hasn't made any difference. Cheers.