Happy 4th fellow Americans! Everyone else, hello! I have a question about the subject cab and others like it (it has a rear port that's kinda small maybe 6"?) Is there a minimum distance that you want the cab from the wall? It really seemed to open up when I gave it 2 feet...but I wasn't comparing in the same room...how much of a difference does it make in your sound when you're 'backed up against the wall' vs. having all the room you want in back of the cab?