I have a 76 model t it was not sounding right and 2 of the volume pots where messed up so i took it in to have it serviced 3 days later amp tech called went over and my god this head sounds good now had 2 wires touching each other fixed that and clipped the white and blue colored wire going to master volume took it completely out of the circiut helped the sound alot and put 3 JJ 12AX7's in rebiased and he checked everything including caps he had never played thru a sunn amp and he was just like holy sheet! lol he fell in love with it and only set me back $138 , anyway just wanted to share my love and excitment with the rest of you.