Original poster: Slurp812 <slurp812@xxxxxxxxx>OK, so I got some PVC, and been doing research on secondarys. It was sugested somwhere that baffles be installed on the inside. OK, so I was thinking of a quick and dirty way of sealing up the inside. What if I were to just fill the inside of the secondary PVC pipe with expanding foam? Do you think that would work, or make it more lossy?