I was quite surprised at how much output the EP400 had compared to the EP350.

No doubt you can get a lot more output with a properly designed 15" driver, but my guess is that the EP400 has a long throw 10" driver in it. The long and short of it is that it depends entirely on the driver design.

Fred

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Blujays1: Spending Fred's money one bottle at a time, no two... Oh crap!