I had been thinking only about compression driver's for the horns with the assumption the lens for cones would be larger than I had envisioned - but your suggestion has got me wondering (just what I need, another thought provoking alternative).I will be asking more about your appraisal of the drivers as I spec and start designing - first off deciding what rule I will follow for horn response and bass box. The price of drivers will probably not scare me off as much as building the crossovers will...
Thanks again Bill - I'll probably FU via Email in the new year.
Henry