I've had reasonably extensive experience with horns - I currrently own a pair of Zingali 3s and I auditioned 2 other brands (SAP and Avantegarde) at length before my purchase. Some years back, I decided to buy a low powered SET amp (I wanted to check out the enthusiasm for these designs) and was looking for an appropriate speaker match. Ultimately, I settled on horns for that reason.
Of the 3 brands, only the SAP presented coloration issues for me, but I gather that I'm less sensitive to mild colorations than some others who participate here. The Avantegardes were appealling but not so much the price tag, so I ended up with the Zings.
After a few years, the issue that caused me to look elsewhere was what I'll call "the dark side" of extended range horns. That is, if the bright side of horns is - as Shadorne noted - lack of compression. All the designs I mentioned are strikingly dynamic at audition, but....
The (sub)woofers are not horn loaded. Horn loading a true low frequency driver is generally impractical, so this "hybrid" approach is common to most extended range horn designs. As the volume goes up, the horn loaded drivers remain unconstrained, while the (sub)woofers compress in fashion that - in my system - was audible and, eventually, offputting. After this discovery, I re-auditioned the Avantgardes at a local dealer and specifically varied the SPL more than I would usually do at such an audition. In the end, I noted a similar, if admittedly subtler, effect with the Avantgardes.
I can't generalize to all such designs, but -in my case(s)- I found the mix of horn loaded upper frequencies and non-horn loaded bass more distracting than, say, a well executed panel with dynamic woofer hybrid (as a reference point). The bottom line is that I now use the Zingalis for background listening - where they sound great, if overkill - because I find them bright at higher SPLs.
I do not intend this to be an overarching criticism of the design approach, merely a response to the OP. For me, that's "why not horns" in my main system.
Marty
