Why were sealed designs not considered until now? That was one of the main reasons why I did not go to Axiom for my sub woofers.
This is a difficult question for me to answer since I wasn't at Axiom when the original EP500 and EP600 were conceived. The EP400 and EP800 have, of course, always been sealed. Really my main focus in redesigning the subwoofer line was to identify areas where performance could be improved and then determine what would be required to achieve those improvements. New amplifier designs with far greater dynamic headroom and a new DSP engine then lead to the requirement for higher excursion woofers which then lead to the issue of port noise in the EP500 and EP600 at these new output levels. All of this together with the reduction in distortion by going sealed made the decision easy.
