NAD, I think?
I'm not sure that modern high end horns aren't performing properly according to their designers, but we all have different ideas about that...
I agree wrt compression drivers and cones, but one way to do it is to use lots of cones, recently saw a setup using 8 15s per side in a slot loaded open baffle... Great Planes Audio is making drivers based on old Altec designs and the Acoustic Elegance woofers are really good too. I'd bet the AER Studio Bass driver is also great, but expensive. My speaker is using a custom 4.5" driver with a 2 gram cone that comes out around 105 dB (with horn), and it's true there's really nothing like it on the current market. I add about .5g of varnish to the cone and machine phase plugs for it, it's really impressive!
One thing about a true horn speaker, it's like owning an exotic pet... not for everyone without the space, money and fortitude! While often problematic, I do think the application of horn speaker concepts to a smaller home speaker holds a lot of promise. I think some previous attempts have been unreasonably bad (A friend has older AG Unos) but better stuff is around these days. I recently heard the AG Duo Mezzo and thought it was far better than previous attempts. Cessaro, I've heard multiple times but never feel like I can get a good handle on the sound due to their turntable only demo policy and limited material available. I'll have to try to make it to Munich next year, it seems much hornier than RMAF...
