Well, this one's not so much quirky as it is unusual. Magnatone (Estey) probably made a few but I've not seen another one like this. It's a PANaramic 1210 -- okay these are unusual but some of us have seen these before -- but with a solid state rectifier and Jensen C12R, stock!!! I just replaced the filter cap can (and bias cap) and determined that the rectifier circuit was incorrect (thanks to some TGP helpers!)...the amp's been using only half the high voltage line and half of its full bridge rectifier all this time (who knows how long?!?), but it's sounding great now. Well at least to me.