Response of the Stage Series four π Speaker is flat as a board. It uses a three cubic foot cabinet tuned to 40Hz.Bottom octave response of Stage Series four π Speaker
The JBL 2205, 2225 and 2226 as well as other similar 15" drivers from various companies also perform well in the same cabinet, so it is apparent to me that these companies have all tried to provide compatible products so each could be sold as a replacement for the other. I see it as the "small block Chevy" of the prosound world.