While the words “phantom power” may conjure up scary images among non-audio professionals, there’s nothing menacing about one of the most convenient technologies to ever accidentally enter the music industry. We say accidentally, because the +48-volt phantom power spec comes from a clever solution Neumann came up with in 1966, when they were contracted to supply the Norwegian Broadcasting Corporation with transistorized microphones that would run off of the 48V power supplies already in place for their emergency lighting systems. The solution caught on, and eventually it became the DIN 45596 standard. Though 48V is considered standard now, operating voltages may range from 9V to 52V.
What Does Phantom Power Do?
There are a lot of misconceptions about what phantom power does. Phantom power is a 48V DC supplied to the microphone on Pins 2 and 3 of the XLR cable, while ground is supplied by Pin 1. It figuratively “piggybacks” on the AC signal and is invisible in operation. The phantom DC voltage powers the amplification circuitry for condenser microphones, and in the case of externally charged capsules, phantom power supplies the charge. Put simply, it’s the power your condenser mics (and occasionally some dynamic mics) need to function.
Can Phantom Power Mess Up My Mic?
Not typically. Normally, the +48V current simply goes to ground if it isn’t used, so unless there’s a wiring problem, you should be okay. The only time phantom power can be harmful to a microphone itself is if the voltage is applied to a ribbon microphone through either an incorrectly wired cable or by mic patching via a TRS cable. In those cases, the ribbon element itself (often as thin as 100th the thickness of human hair) may be damaged.