In my never-ending journey to understand vintage electronics, I find myself looking for footholds, concepts I do actually understand, to help me decipher what I don't understand. When I was a photographer, someone told me, "All a camera does is hold the film flat so that the lens can focus an image on it. You are painting with light." I never forgot that, and understanding the overall concept really helped to guide me through f-stops, shutter speeds, film speed, etc.
Can anyone explain what happens to electricity as it enters a vintage receiver/amplifier and makes its way through the various circuits? Feel free to explain as if to a small child: Mr. Electron is in a big hurry! He is also very lazy and will always take the easiest, quickest ground, even if the path is through your finger! What in the hell is going on in there? Why is there a bridge rectifier? Why do we need so many damned caps?
Even if it pains your great mind, please oversimplify so that a mere mortal may comprehend what's going on behind the green curtain (Wizard of Oz reference; nothing naughty). I know the difference between AC and DC and not a heck of a lot more than that.