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Help I got a big time Hum in my system

I just put my HT system together. It consists of Aerial fronts Aerial rears and Aerial center and Paradigm 15 sub...power is Classe ca300 for the fronts Parasound 2203a( 3 channel) for the rears and center.The pre/pro is an Aragon
Soundstage....Cables are mostly Straightwire.
With that aside I am getting a loud hum out of all channels in all modes....it is always present even when the processor is off. It will get louder when I turn the processor up to about 60 per cent....but in lower volume settings it seems to bee constant. I do not have any power conditioners in the system at this time.....The outlets are suppose to be dedicated circuits.....When I have just the amps on and take off the interconnects to the processor it stops.....Is this a problem with the way the electrician wired my room......I need help bad Please!!!! Thanks
tmoore
danner
202 posts
 
Be sure to use a star configuration where the power cord of each piece goes to a single source of current. You probably know that but just in case I thought I'd mention it.
Good luck.
jvia
195 posts
 
If you have 3 pronged plugs, get enough two prong adaptors and "float" the ground, though it will probably just be the amp that will need floating. If the problem goes away, you need to call your electrician and have him get you better grounding unless you want to keep the ground floated, which is not a real good idea. At the moment it sounds like one piece of gear is not getting good ground. But hey, I could be wrong.
binaural
18 posts
 
Along the lines of Jvia, perhaps your system has a ground loop caused by more than one three-prong AC main cord. Since individual components are connected to each other through their interconnects (and you say when you remove interconnects the hum stops), only ONE component should be three wire connected to the AC receptacle or line conditioner. All other components should be two-wire connected only. I purchased some two-prong ground adapters from Radio Shack and attached them to 2 of the 3 three-prong plugs in my system and eliminated the ground loop and corresponding hum. Of course this will only help in your case if you have more than one three-prong plug in your system. Good hunting otherwise.
stehno
1,453 posts
 
Try disconnecting the tv-cable and unplugging the tv. If this eliminate your hum, then you can fix this cable ground loop hum several ways without costing you any money.

Either ensure that all grounds to all components are using the same ground and/or circuit.

Or disconnect the ground (for safety sake many will discourage doing this) at all outlets for your tv and audio components.
whatjd
1,139 posts
 
Check what Herman says above....most cable TV feeds into your home will ground the cable to the same earth ground(pipe) that the AC input to your home is grounded to. Many cable TV feeds have serious DC voltage on the ground, and thus my be placing a DC voltage on the ground pin of all of your homes AC plugs...causing hum/noise on your system...let alone reducing the overall capibility of your components.
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