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
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That clarifies everything.  I'm not too scared of it, i've done a little bit of electrical  investigation on cars and a little on homes but  I just like being very clear when I do stuff with it!
Ok here is the results with power of preamp and amp on:

hot + neutral = 120.5V+/-

hot + ground = 120.5V +/-

neutral + ground = .05V steady
GOOD NEWS!!!

So I found a proper cheater plug and tried putting it on the tube amp only - buzz completely gone whether the phono pre was on or off.  So it appears the amp was to blame and the phono preamp just amplified the problem.

So now, hopefully, when my new Decware integrated tube amp comes in it wont exhibit this buzz/hum, if it does at least I know its not the AC line.

I want to thank everyone who spent their time an energy helping me out!  I learned a bunch and tracked down my problem.
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