A least favorite subject Ground loops

[Pelliott321]

Tom I know about the dangers that is why I don't want to cheat.
I did try my cart monopoly blocks and hum was there.

[SoundMods]

I could not find the original post on DAC generated noise but I was using a USB DAC with my laptop to feed an amp with unbalanced inputs. The PC noise was filtered to ground by the power supply internal noise filter and was picked up by outer shell of the amplifier inputs. When I put a cheater on the PC power supply the noise went away. Note that this was not AC hum but higher frequency switching noise. But it did illustrate that a noise filter in one component can put out various kinds of noise on the ground line.

Above all, remember that using a cheater can be fatal if you get a fault from line to chassis in one of the components and then come in contact with something that is grounded. Definitely can ruin your day.

But he would die with a shit-eating grin on his face because the music was so awesome and noise free.

[Jim G]

....I did try my cart monopoly blocks and hum was there.

Thanks. Just asking the obvious. Are the amplifier and preamp plugged into the same outlet? Not just the same circuit, but the same outlet/power strip? I've experienced hum from that before. Plugged a powered sub into an outlet (same circuit) across the room and got wicked hum. Plugged into the same power strip as everything else, silent.

Are you using Audiophile power cords? If so, try a generic set of power cords. I've seen those introduce hum.

[Pelliott321]

It was Cary monoblocks
Yes believe me I tried it all I went back to standard cords fearing my 10ga diy cords slipped a gear