XLR 3-pin Pinout
The standard balanced-audio connector for microphones and pro-audio interconnects.
Overview
The 3-pin XLR connector carries one balanced mono audio signal and is the backbone of professional audio. It uses a differential pair plus a dedicated shield, which rejects noise picked up over long cable runs.
Pin 1 is the cable shield/ground, pin 2 is the in-phase (hot/+) signal, and pin 3 is the out-of-phase (cold/-) signal, per the AES14 / IEC 'pin 2 hot' convention. Phantom power (+48V) for condenser microphones is supplied equally on pins 2 and 3 relative to pin 1.
Pinout
| Pin | Name | Function | Description |
|---|---|---|---|
| 1 | Shield / Ground | GND | Cable shield and chassis ground reference |
| 2 | Hot (+) | POWER / AUDIO / SIGNAL | In-phase / non-inverting signal; carries +48V phantom power |
| 3 | Cold (-) | POWER / AUDIO / SIGNAL | Out-of-phase / inverting signal; carries +48V phantom power |
Notes
- Pin 2 = hot is the AES/IEC standard. Phantom power applies equal +48V to pins 2 and 3; pin 1 is the return.
Reference: AES14-1992 / Wikipedia — XLR connector· verified 2026-06-27