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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

Showing 3 responses by jea48

jea48
4,266 posts
 
last_lemming OP  265 posts                                              02-20-2017 10:46am

What TT are you using? Cartridge?

I have a Dynavector 20x2L, and the cables are Cardas Clear Light. They have never given me trouble before. I don’ t know if this matters but the noise is coming from both speakers, but I assume if one cable was bad then that noise would affect both, but I really don’t know.


I will try swapping out cables tonight to see if that helps.

//

Did you try what I suggested, disconnect the TT phono cables from the phono preamp? You said the hum/buzz was independent of the volume control setting, so just turn down the volume control and listen if the hum/buzz is still there with the TT disconnected from the phono preamp.

If the hum/buzz is gone then there something between the TT and the phono preamp going on. IF the hum/buzz is gone then I would say the problem, issue, is not between the preamp and power amp.

If the Hum/buzz is still there then the next thing I would ask is how close is the Parasound JC3+ Phono preamp to the power amp?

Try moving the preamp as far away as possible from the power amp. Especially the power transformer of the power amp. Try turning off and unplugging the power cords of any other equipment near the preamp. Only have the preamp, power amp and TT plugged into the AC power.
jea48
4,266 posts
 
One more test.

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.




jea48
4,266 posts
 
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.
The cheater plug on the amp did break the ground loop circuit, but that does not prove the amp is at fault. It could still be the preamp causing 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.

Time will tell.

Good luck,
Jim
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