Typically +48 volts DC found at mixer inputs (equipped with phantom power) between pins 1 and 2, and 1 and 3. This power is used to power condensor microphones and certain active direct (DI) boxes. The presence of the power does not affect dynamic microphones or good passive direct boxes. Called "phantom" because it travels through the same cable as the audio signal and doesn't require another cable or set of wires.
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