Low level Hum in Phono Signal Path

Frepec,
How far away is Your Preamp from the Turntable?

My Rig has a Hum issue... In My
case the phono stage is a
seperate tubed unit,
& the power supply is remote (3+ feet away from the cartridge). However the Tubes are right below the T.T.
cartridge gounded at the Phonostage.
So maybe It is the Tubes causing the Hum?

First, do you hear the hum ONLY on phono? If so, I agree with the notion that it most likely has to do with grounding between your preamp, tt, and tonearm. I am having a similar problem with my newly set-up Technics SP10 Mk2/RS-A1/Ortofon MC7500 rig. I normally run a Lenco/Triplanar/Koetsu combo that has absolutely no hum issues. With the SP10 et al, I get a volume-dependent hum, probably just like what you are experiencing. The SP10 is in a slate plinth which is absolutely not grounded. So far, grounding the RS-A1 tonearm to the preamp (an Atma-sphere MP1) did no good. My next plan is to ground the SP10 to the MP1. The MP1 is a true balanced circuit, and I have never had hum issues of any kind before, so I think I've got to blame the new rig. Let us know what happens if you take some of this advice.

Thanks for the help, even Bob (acoustat6). I guess that was a little redundant. And, by the way Bob, it's Princeton. Just kidding. Let me bring you up to date. Some of you have asked about my cables. Using Tara Labs ISM cables though out. However, the tone arm cables are not plug-in type so they are what came with the 'table. They are shielded, RCA. The 'table is $5000.00, with arm, so I am assuming the wire is better than say lower end but obviously not top of the line either.

I have the tonearm grounded to the BAT PK5 phono stage which is a tube unit. The phono stage is two shelves below the TT as is the Preamp (Mcintosh MC2200). There is very little audible noise on CD mode. By removing and reinstalling the arm ground wire to the phono stage, I was able to lower the phono noise level to about half of what it was. Must have been a sloppy connection. My dealer says that if I can't hear the noise from the listening chair, don't worry about it. It is not annoying but I was interested in what causes this noise and if it is possible to get rid of it totally. From the replies I just read it appears to be a grounding issue. It also appears that I probably can't get it any quieter than it is now, which is acceptable.

Thanks again to all who replied, including Acoustat6.

I don't think this has anything at all to do with cable shielding. Cables pick up RF, not "hum". The term hum implies a 60Hz monotone. RF can include radio reception, hf hash, etc, but not hum per se.

I am also hearing a low level hum, but mine happens as soon as I connect any device. I've tried some of the fixs I've seen here: started by disconnecting the balanced inputs to the power amp (Threshold T-100) and there is no hum, so that means its not from the speakers.
Then I disconnected every component. As soon as I connect any device, (EAR 834P; tube CD plyer no matter what) I get the hum. I've tried cheater plugs, ground wires. Can't figure it out.
Any ideas?