[ponchonutty]

Originally Posted by CBFryman

Marine Grade doesnt warp. period. and it wont swell like MDF. and it is slightly more dence than MDF which gives it a lower FS. so it is technically better. but because MDF is good enough little difference is found.

If you get real HDF, it won't swell or warp at all. I left an old box outside the shop and it rained hard. Actually filled up the box alot until I figured out where it was. Dumped out the water and everythings fine. Marine grade plywood is OK but it is subject to absorbing freqencies in extreme conditions which is not good. For those lower powered subs you guys talk about though it would probably work.