I hear what you both are saying. First I want to make sure I ask every question I can think to ask. Second I have been looking at the design page u have made and I see one problem with it. At 1000 watts it's not a problem with flow but at 1500 plus the air velocity is really high. The amp I have is able to do 2100 rms and I know I wouldn't use the max but around 1500-1800 probably would happen. If we moved up the interior space from 3.8 to 4.8 could I make the port a little bigger and help with that air speed with higher power? I can get away with it box that 5.5 cubic pretty easy after that is where it gets pretty hard I checked my specs again of my space and it's pretty big. 10 depth, 46 wide, 36 tall. I know that is 7.6 cubic but I know one day I want a second one and that space is only 6 cubic space. So max would be around that 5.5-6 cubic box.