It’s a conventional tube amplifier circuit in which the triode ... and the high impedance of its output is brought down to speaker impedance with that mains transformer. Best of all it doesn ...

It’s hard to beat this vintage reel for learning about how vacuum tube amplifiers work. It was put together by the US Army in 1963 (if we’re reading the MCMLXIII in the title slide correctly).

It's an amp and a speaker system in a single device, and it's designed to produce a reasonably wide sound via its 270-degree sound system. It's not going to be as wide as a standard set of the ...