The OEM Power Supply & “Hum”: Inherent Design Issues
cmcwillieb last edited by
I received the second Amp and it has the same problem as the first, so that is 100 percent of the amps I have ordered that have the problem. I submitted a ticket so we'll see if I have to submit another vid to get them to send another power supply. I still haven't received the first, or the bag I paid for so this should be interesting. The second Amp was purchased as a gift so I just need the replacement power supply before Christmas. Preferably Christmas 2020, but this is Positive Grid.
kwillmon last edited by kwillmon
To me it sounded like there were two noise sources, a 60 cycle him and a higher frequency component on top of that. I no longer own an oscilloscope so, I'm depending on my ears. I use LED lighting in my studio which is known to introduce noise back into the AC line and, that could possibly be the a of the higher frequency noise component of not the PG power supply itself.
After changing to a power supply from my laptop that also has an external filter at the end of its DC output line, all noise stopped. I assume the better quality power supply feeding cleaner DC along with the ground which allows the amp's internal filters to work properly did the trick. I'll probably keep usinh the laptop power supply rather than trust a cheaper replacement from PG.