I dont have any direct experience with madison speakers, but thier web site has a lot of info and specs on the components used in their speakers. i have been to steelsound.com where they sell all of these components and it seems like a pretty good deal. build the cabs yourself and just buy the components seperatly. i just built 2 cerwin vega 18" folded horn subs and used the accesories from steelsound to finish them off. for cab building designs and plans just check out speakerbuilding sites on the net.