Balanced To Unbalanced Wiring Diagram. The bottom line in that schematic diagram should not be connected if you want isolation. Balanced xlr interconnects are what many people consider to be a superior connection between components.
A balanced audio signal works with three wires. Includes guides for 7 pin 6pin 5 pin 12 pin 13 pin pin and heavy duty round plugs and sockets. As balanced audio, as opposed to asymmetric, which is referred to as unbalanced audio.