I did listen to the Hawthorn setup, very nice. I wanted to get to John's room, but we had to leave earlish on Sat, and the room wasn't open. I did hear it 2 years ago, so was looking forward to it. I've played with OB a fair amount, so I was curious about Fred's box-only approach. I keep thinking I should drag a pair of OBs back from the garage to my 2nd floor listening room, maybe this weekend I will. The one's I have handy use a vintage EV SP-12B on top (I'm guessing close to 100db efficent) and a Parts Express 15" IB on the bottom - which needs to be bi-amped of course. Room for such a set up is kind of limited, so I'm a bit hesitant to do all the work just to find out it needs more space. In my mind one of the good things about the EV SP-12b's is that it is a single driver (does need a bit of top end help) so it does not have the horn that the Hawthorn setup uses, thus no crossover either. Sweet way to go.