I was just looking around at tubes and what have you. I play a 400+ and will have to change out the tubes eventually. I see 12ax7's and 7025's and ECC83's lumped together often are they all compatible? Also does anybody have experiance with Telefunken tubes? I love there mics, but do they make 12ax7's (or equivelent) or 6L6's? Thanks guys.