I've got a Raspberry Pi 3 and the official Raspberry Pi Touchscreen that
I'm working on building a case for. I've come across a design decision I'd
like a little input on.

I have an amplifier and speaker arrangement to give me basic sound. I'm
using 2 small speakers, about 1" by 2". The speakers are in their own
plastic enclosure with a provision to mount the speaker using a
sufficiently small screw, probably 2-56 maybe 1-72. FWIW, the case will
probably be pine.

It makes sense to make some form of grill or hole in the wood to make sure
the sound can pass unobstructed. I could possibly cut 1/8" wide slots with
an endmill or drill a series of holes. Which would be better, or does it
matter?

Also, I'd like to keep little bits of debris from sticking to the speaker
cone. Would a piece of cotton cloth or something similar work as "speaker
fabric" without affecting the sound too much?

Thanks,

Puckdropper