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One hum problem solved, another remains

I had recently relocated my equipment to another room, where I can now integrate my 2 channel gear into a multichannel rig. In my old room I never noticed any sort of ground hum problem, but I was faced with two when I turned on my stuff in this new setup.

The first one was easy to solve. It was apparent only on my phono input and increased in volume with an increase in preamp volume. Pretty loud, too. It turned out that I accidentally connected the ground lead from my phono cable to my phono preamp. In my particular setup this produces a real buzz. So that one was now taken care of.

The second is noticable on all inputs, does not increase with volume, and really can just barely be heard with my ear about 1 foot away from either speaker. But I don't remember it in the old room. In this new setup the amp is plugged into a different outlet from the rest of my gear. I tried flipping the polarity of the plug on the amp with no success. Every other piece of equipment is on a three prong plug and is plugged into a Wiremold L10320. I don't know if the two different outlets are on the same breaker.

Any help would be appreciated.
tonyptony
tonyptony OP
617 posts
 
Riffer, where did you get one?
Post removed 
eldulcesol
197 posts
 
Tony, you might have a ground loop problem caused by the CATV line. Just get a couple matching transformers, solder one end of each transformer together keeping both lines seperate, tape seperatly, and insert between the cable line and tuner. You will need an additional one foot cable to do this. There is a slight signal lose which you might not notice, depending on how strong the signal is in the first place. If the signal lose is too much, try a Hugfen HF-NS 120 on the rca sound from the cable box to the tv. That worked the best for me. Got mine on Ebay for about $10 plus shipping. Good luck.......
riffer
362 posts
 
I got the Jensen at Markertek:

http://www.markertek.com/Product.asp?baseItem=JEN%2DVRD1FF&cat=VIDEOEQUIP&subcat=VIDPROCESS&prodClass=VIDEOHUM&mfg=Jensen+Transformers&search=0&off=

CATV is easy to check. Like you were going to do above, if the problem is CATV, when you unhook the CATV, the hum will disappear. It will be obvious.
tonyptony OP
617 posts
 
Update: I disconnected the CATV line and heard no real improvement. So I took the next (what should have been the first) step and disconnected / reconnected all my line level cables. I'm assuming it must have been this, because now the buzzing (it is still there) is so low that I have to stick my ear about 6 inches away from the speaker driver to hear it clearly. I may track down that last little bit at some point, but now at least I feel like I can play music without having some kind of anxiety attack.

Thanks to all for the feedback.
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