Love this thread!!
Last October I picked up a SF Princeton. At some point in its life the hole in the speaker baffle had been enlarged to fit a Celestion G12L-35.
According to where I got it, the amp is from 1972, but according to the serial number info on
this site it might be a 1970. Unfortunately, there's no tube chart in the cabinet.
It doesn't really matter whether it's a '70 or a '72, I guess. All I know is that it sounds amazing. With the bass at 4-5 and the treble at 3-5 its clean tones are something to hear, almost ethereal. Like baby bear's porridge, not too hot, not too cold (although if I crank up the treble the amp can get very, well, trebly!)
As I turn up the volume it begins to get throaty at 6. Fully dimed, the amp breaks up incredibly with a warm and punchy bottom that sounds amazing, although it can get a little flubby if playing a humbucker with the guitar's tone turned all the way down. With the treble turned up and the volume at ten crisply played barre chords sound close to early Kinks or even Who (which is a good thing imho!) Yet even with the volume at 10 it will play cleanly with very light picking. All in all, definitely more than a one trick pony, especially when it takes pedals so well.
One question, though: it came with two 6V6s, along with the other tubes. As a complete tube noob, what is the difference between 6v6s and 6L6s?