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Can't tell,if my house is properly grounded

Hey guys, I have a low level hi/low buzz that is coming through my speakers, not dependent on the integrated tube amps volume. It is amplified when I turn on my Parasound JC3+ Phono preamp, but only slightly. I have the power cords going to the same outlet. I tried running their power through my Furman Elite Power conditioner but that changed nothing. I ran an independent ground wire and checked all the components in various configurations to no avail. I disconnected all the tv cable to make sure it wasn't coming from there and that solved nothing either. I turned off everything in the house I could' no change. I checked my ground outside at the rod and it is all solidly connected, however the depth of the rod is unknown.

any other thoughts before I call out an electrician?
last_lemming
last_lemming OP
638 posts
 
I have cable tv and I turned off all lights when I was checking. Nothing seemed to work. I also disconnected the cable tv.  

HOWEVER - I diconnected everything but the amp (and speakers) no noise. 

I plugged in in the phono pre into the same wall outlet as the amp - no noise.

i connected the RCA connects to the amp from the phono preamp- NOISE!

so I guess there's a ground loop between these two pieces, what I don't get is why, both are going to the same electrical outlet. Only when the interconnects are connected do I get the sound.  If I connect a ground wire from chassis to chassis nothing happens. 

Any thoughts?
erik_squires
16,046 posts
 
It's hard to tell if this is really a ground loop or a preamp noise problem.

Try, temporarily only, using a cheater plug on the preamp. See if this resolves your problem.

If it  does, that pretty much guarantees it's a ground loop issue. If NOT however.... it's a preamp noise issue.

E
yogiboy's avatar
yogiboy
5,656 posts
 
@last_lemming
Did you try the polarity reverse switch? If not you should give that a shot!
last_lemming OP
638 posts
 
i did try and the polarity reverse to no avail.

I also tried a cheater plug, but since I didn't have one designed for that purpose on hand I used an old extension cord for 2 prong components. It had a little bump out on the end to block the ground prong so a person couldn't "cheat". I cut this prong off and plugged the phono pre into it and promptly blew the fuse. I'm not sure why, maybe when I plugged it in I had the plug reversed?  Not sure.  
fineito
34 posts
 
Also try wrapping your interconnect with aluminum foil.  It worked for my phono noise problem.  You can search and find my prior posts on this solution.
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