I currently have a Beringher - Xenyx X802 mixer and use it to run 2 XLR microphones.

I want to add a third mic and was wondering whether I could use an external phantom power box and connect to one of the other channels which I don't use via a TRS connection.

I am also using a Lexicon - Alpha between the mixer and my mac, mainly for headphone monitoring, this has an XLR input, but I would rather have all 3 Mics going through the mixer if possible.

I am new to podcasting and have very little experience with studio equipment of any kind so any and all help is greatly appreciated.

  • Small world. I've got a 502, and I'm wondering the same thing about adding a second mic!
    – jpaugh
    Commented Jun 21, 2017 at 17:51
  • Welcome to Stack Exchange! Did Marcks' response answer your question? If so, you should mark it as the accepted answer, by clicking the checkbox beside it. (If not, ask for clarification in the comments under his answer, or add supporting details to your question.)
    – jpaugh
    Commented Jun 23, 2017 at 21:16

1 Answer 1


You can, but it is not ideal. The remaining channels on your mixer don't just lack an XLR connector, they also don't supply phantom power and they expect a line-level input. A simple XLR to jack adapter will not suffice.

To use a third microphone in this setup, you will have hook it up via a separate pre-amp to boost the signal up to line-level. The quality of the pre-amp greatly affects the sound, but if you plan to record speech, a cheap one will do just fine. It doesn't need to have a lot of features since you're still running the signal through the mixer, but if your mics require phantom power, do check whether the pre-amp can supply it.

In all likeliness, you'll end up spending more than if you had bought a more expensive mixer to begin with. This is why you'll often hear 'buy the best you can afford'. You're wasting money buying equipment you'll have to upgrade anyway.

Alternatively, you could simply plug the third mic into your Lexicon Alpha. It may be impractical to have the mix controls on separate devices, but this setup will work.

An external phantom power supply by itself definitely won't. It's not clear to me whether your mics even require phantom power, but without passing through a pre-amp, the signal into your mixer still wouldn't be line level. Depending on the wiring, you could get no signal at all, or a very weak one with the left or right channel inverted or missing.

  • "...was wondering whether I could use an external phantom power box..." "The remaining channels [...] don't supply phantom power..." You seem to know what you're talking about, but as a beginner, I'm afraid to use your information, because you don't seem to have read the question.
    – jpaugh
    Commented Jun 23, 2017 at 0:16
  • 1
    @jpaugh: Thanks, I've added some details on the proposed solution to make it clearer I had in fact read the question. =] Commented Jun 23, 2017 at 9:48
  • So, you're saying that you need a pre-amp to descramble the audio from the phantom signal? I guess I shouldn't assume an external power source would do that. That must be the source of my confusion. (Thanks for being such a good sport about it.)
    – jpaugh
    Commented Jun 23, 2017 at 14:08
  • 1
    @jpaugh: The phantom power is a bit of a red herring; a proper supply provides 48 V to the mic, not to its output, as that could harm the equipment. Microphones generate a very weak (mic-level) signal though compared to line-level devices like mixers, recorders, media players, keyboards... A pre-amp is used to boost the mic signal to line-level. The Xenyx has those built-in, but only on the inputs labeled 'mic' on channels 1 and 2. Moreover, TRS jacks are often used to carry unbalanced stereo signals. If the mixer expects that and receives a balanced mono signal instead, stereo issues emerge. Commented Jun 23, 2017 at 19:42

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.