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
who performs an inspection of the property on behalf of the buyer. If the inspector determines that work was done without proper permits and inspections, it's a huge red flag that can not only delay a sale, but require that permits and inspections be done after the fact. Was electrical work done behind Sheetrock that's now been sealed and painted? The electrical inspector can insist that the wall be cut open to reveal the work and prove that it was done in compliance with code. 

This part is true in my city. The difference is that the inspector is hired by the buyer and his real estate agent.

As I stated earlier, I hope I'm wrong about how the subpanel was wired. I asked him at the end of the job, maybe I misunderstood. One thing I do remember is that he said new code requires 2 grounding rods.

The name of the company is Generation 3 aka GEN 3 in Philly. Started out as a son, father, grandfather business with very affordable rates. Not so anymore.
I will report back with my findings.


@lowrider57 
Don't let it get to you. Your electrician probably did everything to code.
B
gdnrbob
Your electrician probably did everything to code.
We already know that he didn't follow code. The electrician didn't get the required construction permit and the project wasn't inspected by a city official before it was put into use.

I heard from my electrician and all is good. I copied the instructions posted by @jea48 and @almarg and sent an email. He said that the additional wiring of the new panel matches jea48's information. One exception is that he believes the 2nd grounding rod should come from the subpanel, rather than 2 rods from the main circuit box. (new code requires 2 ground rods per residence).

So, Jea and Al, thank you again for the time you spent dealing with this issue.

@cleeds ,
the project wasn't inspected by a city official before it was put into use.
Inspection is done at the time a house is being sold during the closing process; Title search, Home Inspection, and Pest Inspection are required. The buyer may use an attorney or a realtor for the closing process and must hire the certified building inspector.

As far as permits, I saw the law that you posted, and I know it applies to construction or an addition to a residence, but my neighbor and I both have had electrical and plumbing work performed without a permit from a licensed contractor.


Oh, and @jea48 , I have a 2 phase panel with 60A service (small row home and still meets code). Electrician installed a 60A Double-pole breaker in the main panel, then ran wire in a conduit to the subpanel.
It's about 5" to the side of the main.