1 (edited by Maddcow 2020-02-27 00:15:35)

Topic: UFX+ and noise from phantom power

Hi all. I got a UFX+ at the end of last year and have done a couple of gigs whereby there was a LOT of white noise coming from my XLR outputs. After extensive troubleshooting, I found that the XLR lines were being sent phantom power from the FOH desk and as soon as phantom was turned off, the noise immediately stopped.

First of all, can my UFX+ be damaged by having phantom power sent to its XLR outputs?

Second, why is there noise when phantom is being sent to my outputs? That’s never happened to me with other audio interfaces and digital mixers I’ve used.

Cheers
Gary

2

Re: UFX+ and noise from phantom power

The UFX+ has a rigid protection circuit at its XLR output, that limits Phantom power to 18 Volts. and then uses capacitors rated 35 Volts to keep any outside DC reaching its internal electronics.

The noise might be coming from the phantom power supply as it is highly loaded by the protection circuit.

Regards
Matthias Carstens
RME

Re: UFX+ and noise from phantom power

Ah ok. I was really hoping that the phantom power hadn’t damaged my UFX+ but with the info you’ve provided, I can’t see how it could have.

Thanks MC