During a chat yesterday about how to get VERY deep bass into my room, Nathan (NFordEnfield) came up with what appears to be stunning idea for an infinite baffle sub. The Chimney I don't have space beneath the floor and the ceiling is vaulted. The fireplace isn't needed at all and it wouldn't be too difficult to put a cover on the top that would allow air but not allow rain in. Any immediate problems spring to mind here? If not where do I go from here? I'm thinking of this as a supplement rather than a replacement for a pair of hefty subs. The room's volume is 12,500 cubic ft. I just measured the opening and I could comfortably fit up to a 24" driver in there Any thoughts from you DIY sub makers out there? Mark.