Tube PHONO preamp interference - RFI, EMI, bad grounding?

I'm sorry if I am beating a dead Horse. I feel you shouldn't have to sacrifice good quality sound. I must restate that you should look for the source after a reasonable effort to protect your equipment. In doing so I would first follow up on your failed effort of putting a pan over your equipment and actually try to build an impromptu 'faraday cage'. the theory isn't that hard and some light reading should provide you with some inexpensive solutions. Once you find where the noise is entering your system, you can research what type of source might create this type of spurious signal. Also though unlikely look into all of your equipment power supplies to see if you have a failed filter. Even a $1,000 power supply could have an occasional bad capacitor.

@filipm

I doubt there’s this much noise in your power line that would cause this. The power supply in the EAR would take care of that. Your phono amp, tubes or cables act as an antenna that’s mostly what it sounds like. But anything is possible.

Also, just some notes from my experience rolling tubes…

I’ve tried Mullard, Tung-Sol, Gold Lion and JJ 12AX7 current production tubes in the Rogue ST-100 tube amplifier I had at the time and liked the tone and overall presentation with the Gold Lions the best. But every component is different so until you hear it for yourself you’ll never know.

@audphile1

I get all kinds of responses that often oppose each other. If I followed everything, it would mean not to try anything at all. It might be ridiculous it’s the power line but I have to be sure.

I have read one thread here on Audiogon few weeks ago and someone stated he gave up after several months of investigation and got a solid state preamp.

It was here -

In this case the victim recognized the radio signal and it was picked up by the turntable. ;) the final solution was grounding. He even says "braided ground wires". I was told that it doesn’t make any difference if a ground wire is braided or not. Also that it doesn’t matter where you place the ground wire - because the components share the same ground.

@esarhaddon I have had this problem since I received the EAR phono preamp few months ago. I used to have a Bryston B60 integrated, at the time, I had unplugged everything, leaving all the sockets in the apartment empty. Even the fridge had to wait. I only plugged the Bryston and the EAR phono. It didn’t help.

I don’t think there’s any defective component nor is the phono preamp. It’s simply a signal from the outside. Could it be picked up by the power cables? Probably not, right, it would be the same as if it was coming from the power line.

I think if I placed my cables into a copper sleeve, grounded the sleeve and made another cage for the preamp, then it could work.Maybe the ferrite rings would do the same job as a copper sleeve.

Tube shields might help but only vs airborne RFI or EMI.

I doubt tube rolling is going to help.

SS devices are as susceptible to this problem as tube devices, possibly more so because of wider bandwidth.

Can your phono really be powered by a 12V battery? I’d be surprised.

Tube shields or Faraday cage plus ferrite beads on ICs and AC cord ought to have at least an audible benefit used together.

very late at night or very early morning, do you still have this noise? If not, then I’d suspect someone in your building is the culprit.

The powerline as a source is not at all ridiculous.