The guys at ProSoundWeb are working on an interesting subwoofer called the LAB Subwoofer. The design is free and anyone can build it. They have a dedicated forum for this subwoofer, http://www.prosoundweb.com/community/forum.php?board=3 Its a dual 12" driver horn loaded subwoofer, 22.5" wide x 45" deep x 45" tall. I am looking for a very high output subwoofer to be used for mostly demos and partys, I want my living room to have the same sort of hard hitting bass that is usually only heard in cars with massive stereo systems or some really nice clubs. Here Mark Seaton talks about how this sub could work well for HT use... I am considering building one or two of these for my room for an extremely high output music only subwoofer(s). I do not want to give it any assistance so I would just cut it off at 30Hz. I though I would start a thread about this subwoofer in case any of you guys are looking for extremely high output. I am not sure what one or two of these subwoofers would put out from 30Hz on up but I have read each sub would take about 2000watts and with the efficiency around 107dbs we are talking major output. I am guessing a pair in my room would put out ~21 more dbs than my dual Tempests from 30Hz on up..thats about 133dbs in my room...this should give me the chest thumping bass I am looking for. The main negative to this project is that the boxes seem fairly complicated. Positives are that a pair of these stacked and firing into a corner would take up very little space and this is a fairly inexpensive subwoofer. I think this is the project I have been waiting for but I am still not quite ready to commit because the boxes look like a pain, I would appreciate a more detailed 'how to' on building these enclosures.