What kind of pillows do I put in a Dayton subwoofer and how?

[SunnyOctopus]

I heard there was some mod to increase the performance of the subs. Are there any instructions or guides on the process? Thanks!

 

[Stereodude]

I'd suggest reading this article.

Supposedly fiberglass works even better, but I've never found any information suggesting exactly how much fiberglass to use to get what effective improvement.