Majik, don't lose sleep. This is a new product and you clearly got a bad one, either through damage or other problems in production. What you are describing is not a performance issue. Two drivers in a box that big with even a crappy amp would give a significant thump even if built in my garage. It would not compare to a good design, etc., in critical listening, but Bob Marley would be shaking some stuff. And we know Axiom can make subs, the ep500 and 600 owners have made that clear. Just write this off as a pain in the arse in life and try another (assuming you don't have to pay shipping). I'm guessing the next one will rattle Bob's dreads as expected.

Good luck and let us know how it turns out.

Panny 3000 PJ, 118" Carada, Denon 3300, PS3, Axiom QS8, PSB 5T, B&W sub, levitating speaker wire