Phantom power, as the term is used with audio equipment, is DC voltage transmitted through microphone cables to operate microphones that contain active electronic circuitry. It is most commonly used with condenser microphones and active direct boxes.
Phantom power supplies are often built into mixing consoles, microphone preamplifiers and similar equipment. In addition to powering the circuitry of a microphone, traditional condenser microphones also use phantom power for polarizing the microphone's transducer element.
Continuing from our prior post on microphones with a video from the EEVBlog and Doug Ford, the former head designer at Rode Microphones, they now move on to how microphone phantom power works.