December Birthdays 
The Bassman discussion reminded me of somthing to watch for when shopping for deals on old Fender amps. I don't have a lot of Bassman experience, so I'm not sure it applies to it (I think it doesn't).
The big amps (Twin Reverbs, Shoman) were the first to get different cicruits, so when buying a big silverface, be aware that even if it's early, there's a big chance it's not a Blackface AB763 circuit in a Silverface package. The first years (the ones with the aluminum trim around the grill cloth, up until 69, IIRC), have a weird partial cathode bias circuit that's called AC568. In stock form, I think it sounds worse than later stock form Silverfaces (well, excluding the Ultralinear models).
However, an amp tech that knows what he's doing can convert them over to Blackface specs pretty easily. So, if you get one, and it's not sounding great, don't waiste your time rebuilding it to stock specs, instead rebuild it to Blackface specs.
When I got my amp (a 69 Twin Reverb that someone put in a crappy head cabinet), my first amp tech (later to be replaced by somone better), was pretty surprised to see the weird circuit that was different than the later Silverfaces that he knew.
So anyway, just wanted to share the info.
Ran
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The intent, we believe, was to dampen some of the large transients that were allegedly swamping the tubes and transformers at the cross-over point. Remember, these were hi-fi yokels that were brought in by CBS, after Forrest White and the rest of the remnants of Fender had left. These guys couldn't've spelled "professional musician's amplifier" if they'd had one hit them in the head!
