Is regular 3/4" plywood (5 layers) ok for a sub enclosure? I plan on bracing with either the same plywood or mdf... I have an all mdf box already built for my av12, it's 3.5 cu-ft. Problem is it vibrates and rattles once the volume reaches moderate levels. When you put your hands on the side panels, it feels like the box is being pounded, like somebody punching it from the inside. It's a mess since some of my cuts weren't flat and I didn't brace it properly... So I have a couple choices now... build a new box, with flat/perfect cuts out of the 5 layer plywood, brace it HEAVILY and properly. Or Tack on the 5 layer plywood onto the outsides of my current all mdf box. What do you guys think?