speaker magnet proximity Question

[pango]

Maybe a dumb question, but I'm rehousing an amp that I rebuilt (an old silvertone), and was wondering if there are drawbacks to having the metal chassis close to the magnets of the speakers. There's no heat issue, as the tubes will be a good distance away. Transformers too. But I was wondering if having the edge of steel chassis very close (as in less than an inch) from the speaker magnets might induce some type of hum. I have a fairly thick (approx 1/16 in.) sheet of aluminum that I could slip in between the magnets and the edge of the chassis. Would there be any point to that?

Again, heat is not a problem. The tubes are oriented away from the magnets/speakers, and I'll be installing a cooling fan to blow across the whole thing anyway.

Thanks

[planet10]

i wouldn't fret.

It is the transformers that might be affected by an external field. Aluminum won't screen it if you have an issue. You need to use something magnetic.

dave

[poynton]

Hi.

It's an interesting topic.

After all, there are now 'snake-oil' salesmen who will sell you various cds and other tools to demagnetise all your audio chain (and presumably your speakers) for a not so small sum of money.

Magnetic fields MUST have an effect on current flow in tubes.

Andy