[KU40]

Interesting question, not one that I've ever seen asked or addressed.

My logic refers me to a downfiring home audio sub. The floor is
obviously 0% air movement through, but the sub is up off the ground by
a couple inches, and that works just fine. So I would say that if you
can raise the grill above your sub by 2" you can put any design you
want in it. If you don't want to have it raised that much, then I'd
say size of the holes in the grill will be more important, with it
needing more hole surface area as the grill gets lowered closer to the
sub.

so if you can raise the grill off of the sub by 2, maybe even 3", you
wouldn't have a decrease in volume, no extra strain on the voice coil,
and no change in resonant frequency.


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KU40