Standing Waves in Mid-Range Pod?

I've built cylindrical pods (completely sealed enclosures) for 2.5-inch midrange drivers that will mount on the dash. They'll be playing ~700-4000hz.

Would it be worthwhile to treat the inside of the enclosure (e.g., put foam on back wall or add Polyfil)? Do you think it would reduce the possibility of standing waves in the enclosure or affect the sound in any way?

Thanks in advance for your input!
Thanks, Perry. No, they're cylindrical with a back. So, really, they're small sealed enclosures.

If you had to choose between foam and Polyfil, which one would you do? What's your rationale? How might they affect the sound or output?

Really just trying to learn more here...

Yes, they will have both even and odd harmonic eigenmodes, so normally stuffed with polyfil/whatever and more recently with shredded jeans becoming popular. I grew up with fiberglass insulation and would us it today if still building since you don't need as much for a given stuffing density.

Regardless, as Perry noted you want to insure it can't get into the open back driver, i.e. historically with cheesecloth loosely draped/stapled over the driver(s).

Some general guidelines for stuffing.


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