You have the right idea. Listen to the driver free of extraneous additions to the sound.

By the way, the M252's are now fully broke in and the midbass hump has subsided quite a bit. The sound is unique from these(6 cu' sealed), the response is decent to just barely below 40hz in this configuration.

With open baffles this high "Q" (Qts - .564) should be a great performer down to around 60hz(my guestimation). With proper placement might gain down to around 50hz.

Can't wait to hear Bill's impression of your current setup!

Regards, Ron