well, i finally got into this amp, life sort of intervened and kept me from working on it (crashed my bike, broke my collarbone and suffered nerve damage affecting my left index finger...fretting hand....sucks) but i just took a good look at this yesterday. turns out, it was in the tone circuit. there was a cold joint off the .022uf cap coming off the bass pot. resoldered the joint, bass control now does something...amp has bass and "life." also i retubed the whole thing and am currently waiting on a few caps to arrive to do a cap job. i bought the 30/20/20/20 @ 550v can cap CTech is selling on ebay. anyone used them?