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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
 
With only the preamp connected to the power amp, TT not connected to the inputs of the preamp, unplug the preamp from the AC power. Turn on power amp and check for the buzz/hum
Did this and no hum.  I'm not clear what that proves or disproves, if the preamp isn't plugged in then the ground isn't plugged in and no ground loop can occure. 
last_lemming OP
638 posts
 
I just unplugged everything but the amp. I didn't notice before the same buzz/hum is there but bearly audible. This make me think that the noise is in the AC line. The phono preamps amplifies small signals so is it possible this bearly audible sounds becomes easily audible once it's boosted?
asvjerry's avatar
asvjerry
4,597 posts
 
Just to add to the general dust cloud that the OP is removing hair over...

I had a persistent 60cps 'hmmm' that sent me on a search & destroy mission.  Went through the usual 'disconnect this/eliminate that' routine on my system to no avail.  Moved on to the ac circuit, unplugging or disconnecting everything, including the GFCI 's that were part of that line...

It persisted.  Visions of 'Reddy Kilowatt' giving me the middle finger salute.

Spouse said "Why don't you try a different circuit?"  Since I subscribe to 'the women are smarter' theory (as they've got us pretty much where they want us), I got out the extension cord...3 wire, of course.

*Poof*  Gone.  Beats me as to why.  Only operative reason may be a noisy breaker.  Since the existence of the new extension cord isn't a tragedy nor an issue I'm in no rush to buy a new breaker, BUT...

It could be that simple.  Easy enough to try, can't hurt to do so.

Good luck.  Spouse got thanks, big hug and kiss. ;)  She likes my hobby...she likes how it all sounds as well although the complexity of 'the mains' confounds her.  So the project at hand is to develop a simple 'work-around' for her to enjoy the solution as well. *S*  Marital bliss requires maintenance...;)
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lowrider57's avatar
lowrider57
5,417 posts
 
@last_lemming ... jea48 was very helpful to me in finding the cause of hum in my system.
I just unplugged everything but the amp. I didn't notice before the same buzz/hum is there but bearly audible. This make me think that the noise is in the AC line. The phono preamps amplifies small signals so is it possible this bearly audible sounds becomes easily audible once it's boosted?
An easy test would be to use a heavy-duty extension cord and run it to a receptacle on a different breaker, (as mentioned above). Then listen to amp only.
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