Soldering mu metal...

[Nick]

Interesting. So I can solder directly onto it with no fear of permanent damage, being careful not to taint the plastic box its stuck to, or even soldering fly leads to the individual pieces before sticking them down.

I suspect that a "star" earth will be the most effective, avoiding loops that might draw EMI onto the earth.

Next question: SHould this earth be the signal ground for the audio stages, or mains earth? I suspect the latter...