I am building a set of subs for my theater. I've done a couple of loudspeakers in the past, but this will be my first attempt at subs. I picked up some (probably not the best) 12 inch infinity drivers which I will use for the project. I figure I can always use better drivers later with minimal cabinet changes (added baffling, for instance) if they deserve it. I have four of these twelves but will probably just build two boxes for now. I plan to use sealed enclosures because I want the highest clarity and detail from the final product. I have a set of five Martin Logan speakers with which these subs will be paired. I have been reading a lot. Probably too much. My plan has been to build an internal cabinet using three-quarter inch MDF and clad the thing with an outer shell of half an inch of some hardwood (maple, zebra, whatever, something handsome) so that I can work the outside and corners, make it look nice. Then some heavy brass feet with spikes and all should be good. It will be a passive box. I will be using some very powerful (and clean) external amplification to drive them. (With all the do-dads available to isolate gear from vibrations and to remove the resonate vibrations created by electricity, why would anyone want to put an amp in the most vibratory locale in the home?) According to these folks: http://mapleshaderecords.com/index.php air dried maple has magical properties that give more musicallity when used in certain ways. For instance they make plinths to place your speakers or your amps upon. They go into detail on the site and it's quite interesting reading. (I'm thinking I'll use their carpet spikes for the boxes.) Why not maple for a cabinet? Anyway, what kind of materials should be considered for building the box? I know that high-end loudspeaker cabinets tend to be made from MDF (with a veneer). I figured that dense was better, but having done some research at the lumber yard and having done all this reading I'm less sure. Let's have some lively debate. I expect that their must be a dozen different oppinions on this one, so let's have some of that old life-experience come shining through. Surely plenty of folks out there have built from different materials and have 'performed the experiment'. Besides, my brain is tired.