Low level Hum in Phono Signal Path


There is a distinct low level hum noise evident through my speakers when the phono mode is on. Can't be heard from the seating area but can be heard when your ear is in front of the speaker, either side. This noise is also dependent on the volume; the higher the volume the louder the noise. What is causing this noise and can it be remedied. (Equipment involved: BAT PK 5 phono preamp, Transrotor turntable with Benz Micro Ruby 3H cartridge)
frepec
Sounds like a potential grounding problem. If your tonearm interconnect has a ground wire, connect it to the ground screw (or a chassis screw if the pre doesn't have a dedicated ground screw). Then, get a ground lift plug and put it on the AC cable of your Power amp. Leave the ground on your preamp AC plug intact. Try that and see what effect it has. I've found more than once that leaving the Preamp grounded and lifting the ground on your power amp will resolve most grounding and hum problems.
Acoustat6-Yeah, nice. The guy's trying to explain, in detail, his issue, and he's mocked for his efforts.

I'll assume you're a Community College graduate, so I'll explain this like I'm talking to a six year old: believe it or not, there are 'hum' issues that are steady-state, with no volume differential dependent on gain. Hence, the OP's clarification.

Hope that helps...
I've had this problem a lot on various vinyl rigs I've tried, and I think this is a pretty common issue. I've had varying success in eliminating it and am hardly an authority, but here are some things I'd suggest:
- check the ground from your table to the preamp - make sure it's good and solid.
- check whether the position of your table with respect to your preamp makes a difference and relocated it accordingly.
- get some Craig DeOxit contact cleaner and apply it to every contact in the signal chain - headshell connections, interconects and ground.
- make sure the TT ground connection goes to your tonearm as well as the TT subchassis.

If you can't hear it from your listening position at normal listening levels that's good, and if you can get it cleaned up so you can't hear it at above normal volume levels (ie from your seat, with nothing playing, volume setting higher than normal), you may have to be satisfied with that. This is because you may reach diminishing returns, and IMHO this is just the fact of life with certain arms, cartridges, preamps, and the combination of them. You're likely to have more of this hum on vinyl than with CD or other inputs, even under ideal conditions. The alternative is swap components.

PS - johnbrown - good on you for calling out acoustat6.
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.