Experiences with mu-metal

What are your experiences and results of using mu-metal shielding?
I’m very interested in the best approaches to utilize this material, and also how it shouldn’t be used.

It doesn’t eliminate magnetic fields, it redirects them somewhere if you use it inside a component. To my humble knowledge you should know where to use and that it doesn’t do any harm somewhere else (some parts might get hot when completely mu-covered or magnetized when applied with magnetic fields coming from somewhere else). So it’s easier to use it in applications less crowded with electronic parts (e.g. block radiation from one component to another rather than blocking radiation from one part of a component to other parts of it internally).

You shouldn’t shock or bend it, as it looses effect then.

By components are you referring to individual passive components or whole audio components also?
I guess having “walls” between each and every device in the chain would be extremely beneficial, especially for phono stages and such.
(Haven’t checked its price per square, might get expensive?)

I don’t remember the price either…I still have two pieces as big as the surface of one piece of equipment…

With component I mean one piece of gear and with parts I mean parts on a board or parts of a circuit.

I remember I used the mu metal when I had an issue with a Gryphon Orestes phonostage. I put a large part of mu inside the housing along the top cover.because I wanted to isolate the unit from external fields. Someone then told me that wasn’t a perfect idea because the behavior inside the unit might change due to the fact that the unit‘s own magnetic field then couldn’t get out anymore either and might cause effects inside no one can guess. I think that’s maybe the main care to be taken: not to encase whole parts of a circuit with it.

As you say for folks who e.g. put a preamp or even a phono amp on top of a regenerator or power amp (and I saw quite a lot of those proud owners of stacked PSA hear here), something like mu metal between might be worthwhile and without harm. On the other hand if it doesn’t hum at all, you probably have no problem.

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