fuses - the $39 ones or the 85 cent ones

Magfan, well your theory fails to conform to the reality, so you need a new theory.

I heard a lecture once at the VSAC in Washington by John Camille about designs that it took to get to 90db signal to noise and higher, which he admitted was God's country. A Faraday cage is totally insufficient. Grounded 1/2" thick mild steel totally encompassing the component with no access for cables or controls and very careful circuit paths, in particular up to caps was what it would take. I went away feeling that our goals are beyond us.

Norm,
In a perfect world we wouldn't need any outside control devices such as AVM. I do use AVM and it is beneficial. I'm fascinated with the idea that a conductor transmiting current or voltage is being modulated by the conductance itself. If this modulation could be reduced at the conductor level itself then the whole pathway would be more accurate. Do tube designers or manufacturers design filaments with the idea that less self induced vibration would make for more accurate reproduction?

As for the magnets they work for me. The shielding may provide even better performance. I suppose I'll construct a shield of brass. Removing the ferrous front cover from my ac mains and hearing the improvement in doing so may have to do with the disruption of the flux field of the ac cables themselves. A non ferrous metal as a cover should make an improvement as well. Tom

Tom, I have been thinking more about this use of magnets to carry ac. I believe that electromagnets use dc to energize them. Would not an ac signal demagnetize a magnet? Is it the magnet or just iron?

Tbg, Please be more specific: What part of my 'theory' doesn't conform to reality? I don't recall presenting a theory.
Please keep in mind that I was NOT advocating a Faraday Cage for home use and indeed am completely aware of there limits and implementation....If I was in RF research (am not) or in Semiconductor processing (I am) I would have use for one.
For a 'vibrating' fuse wire to effect anything is beyond ludicris (sp?) since the microphony effect everyone is fond of quoting has to do with the emission and reception of electrons in a vacuum tube and the modulation of said emission by the vibration. No such emission and reception exist in a fuse so therefore NO modulation. The time I quoted for an electron being in the fuse wire is based on 1.25" and the speed of light, rounded down. Do the math, please.
Now, can someone Please help me with the magnet thing? I can't for the life of me figure this one out.

Magfan, you say, "I simply can not see how that could effect an electron enough to be audible." This implies a theory. If one hears an impact of the fuse this trumps "not seeing how" it can be true.