Short dumb demo. These things were produced in the 50s, I think mainly as tape player preamps - a simple 12AX7-powered circuit. They are sort of rare but not expensive. Controls are Equalisation and Gain. There's trimpot but i haven't messed with it yet. Output is a RCA socket. The original knobs are super-cool, but these aren't the original knobs
and for more Good Fuzzy Sounds demos see https://stompboxes.co.uk/forum/viewtopi ... 42#p375042