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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
200 posts
 
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

wolf_garcia
4,650 posts
 
I hate hum, put "noiseless" pickups in guitars where needed, spend lots of time locating and removing hum from live concert rigs, and will not tolerate even a spec of hum in my hifi pile. However, I have dimmers all over the place (love dimmers), no dedicated power lines anywhere, utilize an embarrassingly ancient "power conditioner" (ha) in my rig, and have zero hum coming from my humble stereo heap. Zero…I think I'm friggin' lucky…I did have some dimmer related hum in my turntable, but that went away when I replaced the tonearm (Akito) cable with a better shielded Mogami. Really lucky.
whitestix
386 posts
 
I gotta chime in here and say halleluya that you fixed your vexing problem.  I have been plagued with it from time to time and finally have have sold gear to rid myself of the problem.  There are a bunch of very sharp and helpful cats on this forum, you included, that are all about helping a guy sort out problems like you had.  Yeah, hum is bad juju and I am delighted you got it resolved. Mark 

mark_hubbard
46 posts
 
Thank you, Bob! My listening room / living room is at the end of our house where ceiling access is either not available or very difficult. Can dedicated circuits be run *outside* the house to reach our room? If you don't mind my asking, what was the cost of adding 6 20-amp dedicated lines? I'm assuming I will need to replace our panel while we are at it, but I'd love to know at least a "ballpark" price for such work.

leotis
151 posts
 
Maybe I can piggyback here.
I have an Oppo 95 connected to a PrimaLuna Dialogue Premium Integrated HP and Zu Druid. Druid are very sensitive and I had a pretty good hum going. Figured out that if I drop the ground from either the Oppo or the PrimaLuna the hum disappears. Both units are plugged into the same outlet. I plugged both into an Equitech balanced power transformer and figured that might work, but still the hum unless I drop the ground.
I'm a little uncomfortable running without the ground... especially with the Equitech given both power wires are hot.
Can anybody tell me what is going on?
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