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
Amandarae, I'm using PAD Venustas from the pre to the amp. These are very well shielded. But, I am using unshielded Kimber KCAG from the phono pre to the pre. I can replace these as a test with shielded ICs. But if it was coming from this area I still think the hum would be increasing with volume.
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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.......