Apogee Buzz Fix

Open Baffle Apogee Duetta's ?

I met a fellow on Audiogon who had Duetta's, and his bass panels were buzzing badly.
He got a price on new bass panels, but with shipping and installation by an approved installer, plus shipping of his Duetta's to the Installer, there and back, the price was prohibitive.
So, here is what he did. He said he mounted 4 - 8 inch dynamic drivers that were optimized for an open baffle in the space where the bass driver used to be!
He said he used an adjustable electronic crossover that was 24db per octave.
He said this allowed him to take the Midrange Tweeter ribbon down to 250 hz vs the 500hz at 6 db crossover of the original.