Whats causing low hum...

[Grimster74]

As many of you know in my dedicated room I have 2 dedicated 20 amp receptables (sp), one for equipment and the other for the SVS. I noticed since I added the Outlaw 990/7700 combo, there is a real soft hum coming threw the speakers, the only time you can really hear it is when you place your hear right next to the speakers but the hum is there where it wasn't there when I had just the Denon 3805 connected. I'm using the balanced connections which is supposed to get rid of the hum but if I hook up the analog connections to the amplifier you can really hear the hum from like 5 feet away. Is there anything I can add to the system to get rid of this hum or ground loop problem? Thanks.

[danger boy]

sounds like a call to Outlaw tech support is in order.. for some reason their amps seem to be causing a few "minor" problems when connected to their own 990 pre amp. and it's not the pre amp.. since I have the 990 pre amp, but not any of their amps. so go figure. I don't have any of the issues others have mentioned with their amps.

[RuSsMaN]

...the only time you can really hear it is when you place your ear right next to the speakers...

Quit putting your ear next to the speakers, sit down, and enjoy!

The only way to troubleshoot a ground loop, is disconnect EVERYTHING, and start over, adding 1 component at a time to isolate the issue(s).

[wingnut4772]

Hey Grim. I had the same problem when hooking up my gear again. I did some pretty thorough wire management - separating the interconnects from speaker wire and electric cables - and that cleaned it up pretty well.

[tledoux]

I had the same problem with my 7500 connected to my Yammie, but I was
using the un-balanced inputs. So I got the VRD-1FF Model ISO-MAX Ground
Loop Isolator (also available from the Polk Store), and there is not even a
minor hum anymore at all.

http://shop.polkaudio.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=13352&storeId=12352&productId=107359&langId=-1

[adam2434]

I started a thread about this cable ground loop isolator last week: http://www.cencom94.com/gpage.html8.html For some reason, the link isn't working, but the model is the Holland CISP and it is about $12 shipped.

Here's the manufacturer's page; look under filters/diplexers: http://www.hollandelectronics.com/catalog.html

It removed the hum I was getting and is compatible with my analog, digital HD, and high speed internet cable service.

If you have cable hooked-up to your system, try disconnecting it and see if the hum goes away. If so, this isolator is a good thing to try.

[amulford]

What Russ said. Sounds to me there is a loop issue, but where I can't say.