For those who might be interested in an inexpensive line array project, see my latest post about the ART array project in the AudioRoundTable Group Build forum.The ART array is a quasi line array with eight 5.25" Dayton midwoofers and a single Vifa dome tweeter located midway in the woofer array. I have completed two pairs, one with surface mounted drivers and one with recessed drivers, and these have been auditioned by members of the Lone Star Bottleheads and the Houston Audio Society. Members of both of these groups commented very favorably on their sound, and I am well pleased too. The cost for the parts, thanks to a very generous discount from Parts Express, will be about $275/pr.
The total cost to build a pair, including the required two sheets of plywood or mdf, glue, fiberglass sound damping material, etc, will be about $350. You can build the version with surface mounted drivers using only a circle saw, a skilsaw, and an electric drill (table saw and router are optional).