Today's Lesson

What is phantom power? Phantom power is a voltage charge that runs backwards, from a mixers’ input to a microphone, via the same XLR cable that the microphone uses to send signal to the mixer. Power and audio on the same cable. It’s actually called phantom power because when its’ engaged, you can’t even tell that it’s happening. Hence the term- phantom. Phantom power ranges between 12 and 52 volts, but 48 volts is the most common, which is why the phantom power button on your mixer is usually labelled “48 v”.

Phantom power is most commonly used with condenser mics, which require voltage back from the mixer in order to operate. If you’re using condenser mics and they aren’t working, check the phantom power on the channel. 90% of the time, that’s the issue.

Something else to be aware is that if you are cascading audio devices, such as connecting the output of a mixer to the input of another mixer or similar device, make sure that phantom power on the receiving input is NOT engaged. While condenser microphones require phantom power, a mixer output can be damaged by the voltage coming back up the cable into it. If you are cascading devices like this, always check the phantom power status on any inputs to which another output is connected to. Your gear will thank you. 

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