CLIO measurement results for Everest horns available here:
http://audioheritage.org/vbulletin/s...3333#post63333
4660 used them two-way in a limited HF extension (16 kHz) max SPL (99 dB) sound reinforcement application. By contrast, 4430 is 93 dB SPL.
Everest used them for mid/high in a hifi three-way, 100 dB system SPL.
Will they work as a hifi two-way as well? Clearly, we can extend the VHF, but the differentially variable VHF response along the horizontal axis is "troublesome." We'll see. Gotta set me up a turntable (lazy Susan) here to determine what's actually going on....