The main problem with this amp was the unbearable noise due to poor circuit layout and shielding.
Modifications: SS-circuitry bypass switch, reduced gain of preamp stages, reduced attenuation between preamp stages, added bright cap, modified master volume control, and stuck a 12DW7 in V2 to get more clean headroom out of the cathode follower. Also put in a pair of late 70's Russian Military EL84s.