I worked at DEC for about 17 years, and I met and talked with Ken Olsen (AKA KO to his employees) and he was a really nice guy, that rare CEO who would still talk with, and listen to "the little guy" . KO lived a very clean life, never consumed any "adult beverages", but his brother Stan, who had been "number two" in the DEC chain of command, he made W. C. Fields look like Carrie Nation in comparison...
I well remember YDI, in Needham, it was one of my main parts sources back in the late 60s and early 70s. Its good to see that it is still around and hasn't just turned into yet another yuppified I-pod, cell phone and computer store.
Definitely that amp's PSU needs some heftier rectifier diodes, the 4007s will work, but for how long ?....
/ed B