"I did some listening tests of the EP500 and EP600 vs. several other brands during my extended stay at Axiom last month, and I can tell you that the EP500 has greater extension to lower frequencies (and greater output at those frequencies) than the other two subs".

OK, the 64,000 question, what are the "two" subs???????

Sunfire amps & processor Sammy 50" Crown amp 2-SVS SS Maple Ultras, Axiom 60s,22s,150cc, QS8s