I have been without a sub ever since I first purchased my HT equipment and I think it is time to finally get a sub. I have decided to build a sub myself with a 15" Atlas in a sealed box run off of a 250 Parts express plate amp. One question I have for you all is what size recommendations do you have for the sealed box? Also when cutting a hole for a plate amp is it hard to seal it up properly? I know a sealed sub has to have no air leaks or else it will sound off so I was wondering how hard it was to reseal around a plate amp and how to do it. I plan on using 3/4" mdf for build material. Also what sort of internal bracing(if any) would I need?