• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Subwoofer hum (grounding) from dac power supply?

Dec 22, 2023
so i got a new integrated and i do encounter some subwoofer hum, wich i think is a grounding issue maybe?
Chromecast Audio > smsl su1 > Kenwood KA3020 > Elac elx 8080 / svs sb1000

i was able to track down most of it tho and it has to do with my dac for the most part. as soon as i disconnect my dac, the subwoofer hum goes down a tiny amount that i wont even notice for the most part. i invested further and this is what ive noticed.

I have a hate relationship with 99% of usb charger plugs. i bought 15 of them and all of them create some really high pitch noise withing the plug, most people seem to not even hear. i hear it across the room tho. that means, i cant use them. the ONLY usb plug i,ve came across that is silent, is the one from my chromecast audio. in return, i had my dac hooked to my internet box usb port to power to not get that high pitch noise. turns out, when i have the dac hooked to the internet box usb, my sub hums like crazy. if i put the dac into the usb plug from my chromecast and put my chromecast into my internet box however, the sub hum goes away to a minimum. there is still some leftover but i think that has to do with the high level inputs to the sub itself and not with the dac.

1. what can i do to power that smsl without using a charger plug? are there any normal usable power adapters or something that provide better power while being silent?
2. for the tiny bit of rest hum, my amp does have a grounding screw on the back. can i do anything useful with that?
Top Bottom