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

Showing 5 responses by mribob

Thanks...just enjoying my rig now without hum, before I get back on the upgrade train. Still can't believe its finally gone...it was like an ugly wart....and now only peaceful quiet.
Peter;
Good question.
After my electrician ensured that all the three dedicated lines where correctly installed with same phase, and added a dedicated ground rod to just these three circuits, there was around a 75% improvement in noise reduction, but it was still there.
It was only after that I moved all my 'wall wart' power supplies from my three WD portable hard drives, my computer power supply, and Universal remote power supply on its own power strip off a plug being used by 'general room' power, and placed into a second Equitech unit, did my hum completely go away. I was only using one PS Audio P-5 as a conditioner, and I did not have enough plugs to have my entire rig powered by the 3 dedicated 20 amp lines. That has always been one of the tips from the Forums to help eliminate hum and unwanted ground potential differences. I did not appreciate how significant that simple tip would be, nor realize what was necessary to achieve that goal, but I'm glad that going back to basics, and following all the tips produced my desired result.
Best, Bob
thanks for folks for reading this post, and offering appropriate comments.
Cleeds: here is comment from my electrician:
"Regarding the question about being bonded to the main panel ground, yes the new grounding system is also bonded to the main panel, all grounds tied together. So glad to hear that it is working perfectly now "
Ozzy: I was able to listen to my system after all three lines moved to same phase, and prior to new ground rod installed. The ground rod only added a small, but perceptible improvement in hum reduction. I do have a Directv box, which is now plugged into Equitech, as is my Marantz, which only has a two prong power cord...my hunch was that the combo of Directv and Marantz contributed to the hum, and now also using balanced power helps in addition to my other efforts. When I tried to use in line filters on my Directv, it failed to send any video data thru...I think they work best on cable TV systems, not satellite systems, but I am not aware of how your specific solution of ISO-Max works for Directv.
Glad we are now both in the 'hum free' zone.
Bob

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

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...