Interference during sound recording - Back UPS XS1100CI

[Anonymous user]

Hi, I'm Diego from Argentina

It's been a while since I'm having problems recording with my external sound card, a Focusrite Saffire PRO 14 via firewire. The issue is not the Focusrite itself, but an interference generated by the UPS (to which the PC is connected) every time I want to record with a microphone, which appears in the recording.

I leave a video with the recorded audio of the interference, did something like this happen to you? What solution do you think is possible? I can not change the UPS model at this time, I have a Back-UPS XS 1100CI

Thanks for reading.

https://www.youtube.com/watch?v=bAZCBrXPAQU&feature=youtu.be

[Anonymous user · Accepted solution]

What I hear in the video is a combination of AC line hum (the low pitched noise) mixed with the high frequency pulsed battery charging circuit inside your UPS.

Beyond making sure everything is connected to a properly grounded electrical outlet, I'd suggest moving the UPS as far away from the computer and your audio cabling as is realistically possible. Use balanced audio connections whenever possible.

Truthfully, you really might be better served by a 750VA or larger APC Smart UPS. You might find that when your current UPS switches over to its battery, a loud buzz will be present in your recordings. This is a result of the modified sine wave that your current UPS outputs when operating on its built in battery. The 750VA and up Smart UPS models all output a true sine wave, matching or exceeding the quality of the waveform supplied by your power company.