Lead shielding


I have made myself a cable tidy which effectively boxes my loudspeaker cables from my 2 aerial cables, and a phono lead from my TV to my amp. The makeup of my room makes this unavoidable.

I designed it with a view to shielding the TV based cables and running a grounding wire to a rod in the garden. I considered the following:
1. run the cables via copper pipes - grounding the said pipe
2. line the respective 'box'/'run' with lead - ground that.

I thought about lead because I saw a roll in my workshop, and understood it to be an effecive shield
lohanimal
Loh, do you hear any difference with or without the shielding?

Lead seems like a reasonable material to try.

I use Mu metal to shield my noise sensitive low level phono gear, works well. It was designed specifically for this purpose in other applications. I think Mu-Metal uses Nickel and Iron mostly, not LEad.

I have read published data on the internet about measured shielding effectiveness of various materials. A google search might be informative.
Mapman, mu-metal is great for magnetic shielding but it is expensive and difficult to form since after bending it has to be annealed.

Choice of lead is not the best because it is toxic and has high resistivity - 10x higher than aluminum. RFI can get in thru capacitive or electromagnetic coupling. Capacitive coupling can be defeated by shielding but electromagnetic is different story. Non-magnetic copper or aluminum shields don't protect but induced high frequency current travels on the outside of the cable - shield, because of skin effect. For lower frequencies skin effect doesn't work but wavelength become too long for cable to be antenna (Antenna has to be >1/10 of wavelength to be effective). Problem starts when cables are too long.

I would just use good shielded cables and save lead for a rainy radioactive day.
It would be pointed out mu metal is for absorbing a magnetic field not for shielding anything from RFI. If you're worried about RFI I suggest 3M AB5100S. Lead is one of the worst materials ever foisted upon unsuspecting audiophiles.