Dedicated Line Noise Filter?


I don’t know if what I’m seeking exists, so I’m asking the experts.
I have 2 dedicated lines installed; one for analogue, one for digital. They originate at a sub-panel off the main circuit box. The sub-panel is connected by the hot lead and has it’s own ground including a second grounding rod. There is a home surge protector installed at the main circuit box.

I have passive conditioning on both lines for the components, yet I’m still hearing noise thru the speakers (from about two feet away). I live in a city and I suppose it could be dirty power from the grid.
Now to my question; is there a noise filter that can be installed at the site of the circuit panels? My electrician offered a surge protector with noise filtering (plus EMI/RFI), but was very expensive. So, is there a device that can be installed upstream to lower the noise floor?
Many thanks.
128x128lowrider57
Thanks @ivan_nosnibor , I'll look him up.
I don't believe it's component related, but tomorrow I plan on removing all power conditioning and surge protectors to eliminate extra circuits and cables.

I swapped the SS with a tube amp tonight and the same amount of noise was audible.
 A friend suggested the 5 KVA because he knew it was large enough for most audiophiles systems and would not bottom out. Other than that I'm not sure how to figure the needs but I'm sure other more knowledgeable people on Audiogon could assist.
lak
A friend suggested the 5 KVA because he knew it was large enough for most audiophiles systems
5KVA works out to 5000 watts - assuming you have a good power factor. That might be sufficient for a small system, but obviously undersized on even a 15A line.

For $750 you would be done with the problem, rather than adding another component/layer. Even better if you can buy yourself for less.
Your electrician seems to be a good guy, if he lets you provide materials.
Though, if you let him install the brand he offers, then he will probably stand behind it should anything go wrong in the future. I'd ask him why he thinks his brand is better than the less expensive ones.