So I have a PC with all my mp3s on it. It is connected to my stereo with a standard 3mm to RCA splitter cable and then RCA cables running to the stereo.
When I listen to music, I have a very noticeable "hum" coming from the speakers. I'm guessing it's from the whole ground feedback thing that I've read a lot about.
Problem is, the PC is downstairs in the back of the house and the PC is upstairs in the front of the house. I have no way of connecting them to the same electrical circuit.
I'm looking for what I can do to get rid of the hum. I've found that if I turn the volume on the PC all the way up, I don't hear the hum as much since I can keep the tuner lower. But if I want it louder and have to turn the volume up on the tuner, then the hum gets louder.
If there's some way I can fix this, please let me know.
If it`s possible for you to connect a ground wire between the PC and the receiver you should be eliminate 90%, if not 100%, of the ground loop hum. Maybe any wire will do, but I don`t know; I just know that worked for me using a recommended guage, 12 or 14, solid copper wire intended for my satellite TV dish ground which I never did.
As already stated, you defiantly need to ground your amp & pc. I had a ground hum issue in one of our amps and was able to run a ground wire to the A/C outlet which eliminated that issue for me.
On another note, most soundcards in PCs/laptops are not very good (suck IMO). Not to mention that built in sound cards/DACs are prone to interference from other sections of the computer (mains adapter/power supply, etc.). I've even read of people complaining about shielded cards. For this reason I bypass mine by using an external DAC that will not pick up any internal interference. You can research DACs to see what would fit best into your budget and see which way would be the best to connect to the connections offered by your amp (depending on the DAC and connections on your amp's side you can use USB, firwire, S/PDIF).
So is it that one of the circuits might not be grounded at all, or that they have to be grounded together somehow?
Not sure, mine are all grounded back to the same point but one room wasn't and I didn't know about it till I set up a stereo in that room. I'm not sure about your home wiring but mine was just a grounding issue. The A/C outlet was not grounded at all and I was getting a hum from the preamp. I first noticed after setup that a hum was coming from my tube amp, so I isolated different components and checked at each point that I could hook up headphones. Possibly it was more pronounced because I was using an external DAC/preamp and testing w/headphones, but once I grounded the outlet it was completely gone.
The cable is around 75' but I got nice ones from Monoprice. I found that I get a hum any time I listen to anything on my tuner now, not just when it's playing the input from the PC. But as soon as I unplug the white RCA cable from the back, it instantly goes away.
I'll have to look into something like the product you linked. Maybe I can find something at a local Radio Shack to make sure it works.