The legendary Manger driver was crossed over at 200Hz, 300Hz or 400Hz (switchable via remote control) to a very good 11 inch Focal driver, it had a Kevlar cone, cant remember the model number. The bass / mid loading was a great hybrid design. Sealed up to about 80% of max power handling, then a tapered highly resistant tunnel filled with various fiber and damping material....It was designed by Mike of Talon Audio in the US, He called it "Fire Bird" I think.