Thank you all for your thoughts on this. I've built some 2-way speakers with Eminence Kappa Pro 15" drivers in a reflex box crossed over at 800 Hz to Altec 806's on 811 horns. To me they sound just great; very "tight" tuneful bass. I certainly do have to pad the HF drivers down substantially, so I've been bothered by the idea that I ought to build a pair of psuedo-816 cabinets with an equivalent reflex volume to what I have now (about 200 L) to see if I can better match sensitivities and get something even better. Maybe I'll just do it and see what happens, though truthfully I'm concerned about expending money and labor for a less satisfactory result (vis-a-vis the comment about needing to add subwoofers).Thanks again for your thoughts.