Colin: thanks again...I recently picked up a pair of EV HR9040 Constant Directivity Horns in road cases for the PA in my band. I'd like to buy or build a pair of A-7's to go with them. I run a pair of Boehlander Graebner RD-70 6' high ribbons on my home system with a pair of 'Mylar Mover' midbass panels (from an old "Speaker Builder" magazine article), and a pair of folded 14'long /24" diam. sonotube floor firing subs running each a JBL 2225H. This is all powered by a pair of MC240 Macs for the subs and 4 more MC40's for the mids and highs (triamped) using a Berringer 3 way electronic X-over and a Mac C-28 preamp....kicks but for soundstage and power...regards Bill