Originally Posted by Simon - PG Music
I tried shielding one with aluminum HVAC tape - surprisingly it worked VERY well, and I measured something like a 10-15db reduction in noise. I've since done the same with a bass guitar I picked up recently, lined the control cavity with the same HVAC tape, and it helped a lot.
It would work pretty well.

Generally I use aluminium/aluminum foil for temporary stuff as it oxidises and the oxide is an insulator, but provided the joints are well overlapped, there's a degree of capacitance between the layers that helps keep the EMI fairly low.

Screening cans in radios and the like are usually tin-plated brass, which can be soldered together or can have spring-finger contacts to keep good conductivity. The copper foil works well, but becomes quite costly, though I've often used it to seal 'leaky' joints between metal case parts. PC cases aren't always as EMI-tight as one might like.

Meshes and punched holes are OK provided the size of the openings is small compared to the wavelength. If they're a significant part of a wavelength they can actually become slot antennae and potentially make things worse.

Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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