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I finally fixed my HUM! Halalulah, and thanks for tips

Dear 'Goners:
I have suffered with a horrible ground loop hum for years, and I tried many of the fixes I read about here, hired experts to come to house and work with me to switch IC from IC, and no joy.
Finally, after being totally exacerbated, I read some basic tips found on these forums.
1. I have three pairs of dedicated 20 amp lines, had my electrician come out, and move one line to that all three were on same side of breaker box, to keep them in same phase.
2. Had him install dedicated 8' copper grounding rod outside of my listening room, and connect my three lines, as well as my Directv sat dish to this new ground point. My room is opposite end of house, over 60' away from electrical panel.
3. Moved my nosy wall warts, portable HD's for digital music, and power supply from laptop away from my amp and DAC, and moved their power onto an Equitech Q that I was using in a different room, and plugged my Marantz 8802 A/V pre pro into it for balanced power. The Marantz only has a two prong cord, not a grounded 3 prong.
Used a PS Audio P-5 regenerator for my home theater set up.
My Hegel Amp, my Playback Design MPD-5, two powered subwoofers, and now Equi tech and PS audio P5 are all plugged into one of my 6 dedicated 20 amp lines.
When I switched my preamp input to an unused source, and turned up the volume...absolute QUIET...no hum, no tube hiss, absolute, pure, blissful quiet.
Initially I had my Hegel plugged into Equitech, but sound came out flat and a bit lifeless. I plugged amp into empty dedicated line, and now everything that I hoped to hear, I am hearing. Great detail, PRAT, improved sound stage and finally appropriate resolution of fine details and spacial cues that were missing.

Bottom line; all the tips here are valid, and work, if only I had been more compulsive earlier, and not trusted that my power was in phase properly, I could have had more enjoyment earlier.  Trust the process, and don't assume that the power is fine, when it may be the culprit. Keep everything, including computer and wall warts for portable HD's, etc on the same circuits, not on the 'house' line....move the nosy power supplies away from key pieces of gear...and finally...the sound of silence. Dedicated ground rods are worth the trouble.
I am grateful, and just listening to music for a wonderful warm spring weekend here in SoCal. The contributors to these questions are great, and I wish to simply say Thank  you for all previous comments, on other posts, etc...it all is helpful.
Best,
Bob
mribob
mribob OP
229 posts
 
Mark;
I had three dedicated lines run from my breaker to the other side of a moderate sized home, which created 6 plugs ( 3 duplex outlets). The cost for a qualified electrician was around $5-600, this was a few years back, and I live in expensive SoCal...best to get an estimate, but be sure to have him read  some of the forum posts about how critical it is to have them installed with all same phase...one of the best investments I did. Be sure your home ground is also adequate...consider adding a new ground rod, as long as its bonded and connected to main power ground.

Leotis: dropping the ground from the Oppo might not be so bad, as it doesn't draw a lot of power...even recognizing the potential risks of lifting the ground if that eliminates the hum. My two channel rig is now stone quiet with the above modifications, but when I engage my Home theater aspect in an integrated fashion to my 2 channel, I do still have a less annoying  but still present hum....it might be my Oppo 105, Directv, or Marantz 8802. Also to achieve balance audio sound levels, I need to have my Veloce pre for HT bypass set at a pretty high sound output level, the hum increases with the volume output of the preamp. I will try to eliminate that bit when I have more time.
Best,
Bob
Ag insider logo xs@2x
mark_hubbard
52 posts
 

MRIBob,

I came across this older thread by accident this afternoon, and I wanted to thank you for your knowledgeable and kind advice in response to my questions above,

If you are still around and reading this, what does "be sure to have him read some of the forum posts about how critical it is to have them installed with all [the] same phase...one of the best investments I did." mean? What is "phase"? Our two-storey 1850 sq ft house is approaching the age (built in 1991, we think) when I should have the whole house rewired, as we have light switches that no longer work, a sconce  lamp that "blew" the last time we tried it (and there is no power to the lamp now), and funky wiring that the previous owner did on his own, although he had poor skills at best and little knowledge about what was correct when it came to wiring. The original builder did not run enough circuits to the two downstairs bedrooms, so that running a small space heater in one will trip the breaker for both. Our overhead kitchen lighting has visible runs of romex and needs replacing... it goes on and on, but you get the idea. Can you point me towards some of the forum posts you thinkI should read before I start calling electrical contractors in our area?

Thank you again for your generous help!

Mark Hubbard

Eureka, California

P. S. While I'm asking MRIBob these questions, responses from other forum members will also be received with gratitude.

mribob OP
229 posts
 

You should consult a knowledgeable electrician...it seems that your electrical panel is old, and may not be wired correctly. If you have the amps and breaker room to have someone add a dedicated 20 amp line, be sure it is run correctly 'in phase', and see if that helps...

sns
3,209 posts
 

All these things you've done I did diy some years ago, 3 dedicated lines, same phase, drove new grounding rod, formerly whole house grounded to cold water pipe. In my case I ran ground wire to each dedicated box, all exact same length(including main panel ground) so no ground loops due to potentials. Went to linear power supplies, no switching power supplies in my audio chain. Also purchased Trifield meter to find rfi hot spots, moving and shielding high rfi components contributes to low noise floor I have no hum with 104db sensitivity speakers with SET amps.

 

No hum is one benefit of all this work, even better is instant improvement in resolution  and transparency  of one's system.

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