I use them in outdoor PA applications- 1 per side on with a pair of 15" folded horns (40-200 hz) and some large Yamaha radial horns on top- xover at about 1500 to the top. Stack weighs about 300 Lbs per side, about 4 ft x7 ft at the front.Really loud with a stereo triamp rig. (but the tune up CD is always great fun to listen to...)
Larry