Can someone tell me if the EP500 Sub is a "powered" sub? Or does power need to come from the amp or receiver? Sorry for what seems to be a dumb question. How does it compare to the EARTHQUAKE SUPERNOVA MKV-12 POWERED SUBWOOFER?

The EP500 is definitely a powered sub. It has a 500W digital amplifier built in and plugs into an AC outlet (with a big hefty power cord ). I haven't heard the Earthquake line, hopefully someone else who has can jump in re: comparison.

yep, all the Axiom subs have their own amp.

The 500 rocks, can't help you on the earthquake.

The EP500 will create an earthquake! Can't help you otherwise.

The Earthquake is probably closer to the EP600 in specs. The EP600 would have a different reponse and db level because of its larger enclosure.

Call Axiom. They should be able tell you more. Fax them a set of specs on the Earthquake. They will tell you the difference.

Very helpful people, those Axiomites.