Thanks jim p. You are the man!! But Im still toying with keeping the op-amp and I struggle with the technical ability to explain why. I am expecting a pcb in the mail anyday now for the "Professor Tweed". Are you familiar with the circuit? Its featured at runoffgroove.com. Granted it uses transistor instead of op-amp but is similar to what I am trying to accomplish. My point is to let the 12ax7(or 12at7) and the EL84 act as nothing more than the power amp and completely change the op-amp circuit to function as a true pre-amp controlling the gain and drive and eq but with much more finesse than the existing circuit. Except to swap out the tubes, (probably with Electroharmonix), I would like to do as little as possible to the tube section. I will definitely check back over at Sewatt. I didn't see the thread the last time I was there. Thanks again jim p.