My HT setup is a Onkyo NR555, with the subwoofer RCA output feeding into a miniDSP 2x4HD, which then outputs into a Yamaha R-95 stereo amp powering the subs.
There is also a TV and PC on the same circuit. Only the PC has a 3 pin wall connection, and it is connected to the receiver via HDMI.
Without the miniDSP 2x4HD, everything is great, no ground loop (60Hz hum). With it in place, substantial humming. All 3 devices have 2 pin wall connections.
The NR555 and R-95 both have ground hookups. My initial thought was to connect both ground hookups to each other via a short 16 gauge wire.
I just want to know if I am being stupid, and should instead connect each ground directly to the wall ground. I don't want to cause any potential safety issues.
Edit:
Nevermind. Connecting the grounds had minimal improvement. Turns out the PC hooked up HDMI was the primary issue, and just putting the amps on a different outlet (yet same circuit) helped tremendously. Somehow this problem never cropped up until the miniDSP was added.
Going to purchase some shorter RCA cables and a higher quality computer power supply to try and remove the last bit of hum.
There is also a TV and PC on the same circuit. Only the PC has a 3 pin wall connection, and it is connected to the receiver via HDMI.
Without the miniDSP 2x4HD, everything is great, no ground loop (60Hz hum). With it in place, substantial humming. All 3 devices have 2 pin wall connections.
The NR555 and R-95 both have ground hookups. My initial thought was to connect both ground hookups to each other via a short 16 gauge wire.
I just want to know if I am being stupid, and should instead connect each ground directly to the wall ground. I don't want to cause any potential safety issues.
Edit:
Nevermind. Connecting the grounds had minimal improvement. Turns out the PC hooked up HDMI was the primary issue, and just putting the amps on a different outlet (yet same circuit) helped tremendously. Somehow this problem never cropped up until the miniDSP was added.
Going to purchase some shorter RCA cables and a higher quality computer power supply to try and remove the last bit of hum.
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