Mark, as Sat indicated, if all you did was switch to "small" without any other change, the overall bass level would be decreased because the M60s would be doing less in the low bass. So, some re-calibration to increase the EP350's output was in order, but be careful about the "fullness" factor. The sound shouldn't be any more "full" than what's on the recording, so the sub shouldn't be turned up so high that it's heard as a separate source. Of course, as always, it's your money, so adjust things as you like.
