Bob, Roy, Troy, Jim Mc., et. al,
I just did a Google search on tube and rectifier issues with Dynaco designs, blew my little tiny mind and long live David Hafler. (McIntosh never comes up, because I guess nobody wants to admit they spent a fortune on pretty blue meters and they still ain't happy).
Rectifiers are a bitch. Embrace that knowledge. Learn to love the fact that rectifiers are a pain and will get you talking to yourself late at night.
As Brother Bob Latino has suggested, though not in so many words, your relationship with a tube system is a marriage, not a shack-up. You want to listen to sand, get solid state. You want to listen to music, well, prepare to dance all night.
Just to share my experiences with brother newbies, and I had a ham license for a good long time and do know the difference between a 6146A and a preamp tube . . .
Rectifiers suck. Did I say that already?
I never had a problem with them in the ham shack (KB7 GTO) lashed up to a Collins S-line set-up, but in audio systems they will break your heart. They blow up and go away without the slightest provocation.
Witness my yesterday's "listening to background music -- honest!" explosion of the latest Weber. The house went dark, a loud buzz ensued, well, you know the rest.
The Webers are cheap, but after you go through 10 of them or so inside of a year, they do get a bit precious.
Seeing snow on the nearby mountain passes, it was time for a tube-roll anyway. Out went the KT-120s and in went the McShane KT-88s. Out with the -120s went the Webers, replaced by those 6-foot-tall Philips rectifier tubes.
All was well, one supposes.
Except one of my brand-new $50 glow-in-the-dark Philips 5R4GYS wouldn't deliver any volts whatsover, dared John Flue to come up with a value, and of course I've lost the warranty paperwork issued by some coupon-clipper in Amsterdam.
End of story: After ploughing through my box of the big dark scary Philips rectifiers I found another one that could come off at 1.2 volts. So all is in balance as I play Chopin.
Until the next rectifier blows.