Unless I'm wrong (gotta say that a lot) that would be why the Martin Logan didn't have the punch you were looking for. My Cambridge Soundworks sub has a rather large enclosure compared to a lot of 12" subs (other than the SVS monsters), since it's sealed. 'Course, it's got a wimpy amp, so I haven't a clue how to works as well as it seems to to me.

I am the Doctor, and THIS... is my SPOON!