3 pin XLR audio connector with high resistance to interference.
The audio signal is sent over 1 wire and inverted over another + ground (3 pins total). Induced noise on the wires (here simulated with the pulse voltage sources in the middle, green signal) is cancelled out on a differential amplifier at the output (here the resistor values are random since I’m too lazy to look up the specifics, but feel free to comment if you have information on what’s missing/different)
Blue=input
Orange=output
Search “XLR balanced line driver” by Peavey if you want to see an op amp solution to the left input side.