XLR to 1/4" TRS Connector (wired for balanced mono)
The usual way to connect a 3-pin XLR to a 1/4" TRS (AKA stereo jack plug) is to use the following pin allocation:
- XLR pin 1 to 1/4" plug sleeve
- XLR pin 2 to 1/4" plug tip
- XLR pin 3 to 1/4" plug ring
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This wiring configuration gives you a balanced mono audio cable.