Faraday cage to reduce EMI in audio amplifier
western United States.
Problem / Question
The bad power in my house is somehow producing EMI in my audio equipment. Will a simple Faraday cage help? (Using an aluminum metal screen) If not that, then what would be the best, most practical, cost-effective solution to blocking this interference.
* As is usual on S.E., if you think I'm wrong about something, please tell me why.
* I'm not inexperienced with engineering / physics, although not a professional. Technical explanations are welcome but not required.
Story
I recently moved into a new rental house. It has old wiring (pre-60s) which is mostly un-grounded and quite degraded. The landlord offered to ground a few of the outlets, but not replace all the wiring. For now, I'm going to have to live with the wiring as-is.
Why I think this is EMI
* Using an amp with a cord as an antenna, the noise behaves exactly like radio wave reception in a TV or a radio. 859
It changes depending on angle, and dissipating somewhat when I block it with my body.
* I'm using a new power conditioner with ground noise eliminating circutry.
* There was no noise at all, even without the power conditioner, at my last place.
* Several other non-audio electrical appliances around the house hum, and sound quite a bit like the noise I hear in the amps.
* The produced audio frequencies from the noise are all above 500hz or so. It's my understanding that ground loops are usually low-frequency.
* Using other outlets, grounded or not, all have the same issue.
Things I already tried that didn't work
* Plugging in to the grounded outlets around the house using an extension cord.
* Turning off as many things as possible to find the source of the noise.
* Using different circuit breakers, turning off as many as possible.
* Using different combination of audio equipment to reduce noise. Using shielded, balanced audio cables greatly reduces the hum. However, that's not possible with everything I own.
* Standing in such a way as to reduce the noise. This works somewhat, but is untenable. (this lead me to the Faraday cage idea). 98