So I traded for this amp recently. Came to me with all stock tubes. I messed around, tried other tubes. Ended up swapping all of them for something else, excepting (I think) the phase inverter. It sounded quite good to start, sounds even better now. I never use the tremelo, so didn't realize until today that it has mostly disappeared. Very faint, compared to how it sounded when I tried it out, with the stock tubes. (Note: There is only one knob for trem - speed. Intensity must be set somewhere in the circuit.) Do any of you schematic reading folks have a clue as to how I managed to diminish the trem, and how I might correct it? Thanks.