Manufactured electronics were really different in those pre-robot, pre-SMD days. As a musician, I have old amps and synths that are really fascinating internally. My favorite guitar amp is a 1977 Mesa/BOOGIE. There are a couple of "gimmick capacitors" wired into the circuit here and there to control oscillations in the high-voltage, high gain circuits (tube amps have 400+ volts in them!). Someone did those manually, in the shop. Really handmade.