After wandering through Home Depot, I'm thinking about these endcaps for my sonotube: 1/4" plywood + 3/4" MDF inside + 3/4" baltic birch outside a few questions I have: - is it a good idea to glue MDF and Birch together? - do I really need this 1/4" plywood inside? What if I put t-nuts into the birch before gluing? (maybe there are other ways to mount the driver?) How sonic-wise(unwise) is it to put the plywood inside? - I've read a couple of posts here that said that 1 Birch is as good as 2 MDF's, does it mean that 1 layer of birch flushed in will be good enough? Those posts of Greg Monfort and Jack Gilvey have made me worry.