There seems to be pent-up demand to discuss this topic but a reticence for the topic's greatest proponents to hit the "Start New Topic" button.
This thread is devoted to the discussion of horn-loading acoustic drivers, the tradeoffs involved, and the juicy subject of horn-loading efficiency as related to low modulation distortion.
Also note that there are newly posted unpublished articles/papers by PWK on these subjects by mikebse2a3 (thanks MIke...once again!) that would likely make good resources for discussion/argument.
DeanG, John Warren, and Gil: let 'er rip!
Chris