With a sealed, downfiring box, I would like to know what is suggested. In the picture below, the dotted line signifies where the subs are mounted, 1" above the floor. Would it be better to carve out some area where the speaker can have air move freely (in front of the sub, not behind), like article b below? It would seem to me that the top example would constrict air in front of the sub, and muffle the sound since it will be enclosed.