All things equal, horns provide more sound with less distortion. That’s the big plus and it should be enough except that the bandwidth of horns is really narrow compared to direct radiators. Working more toward the subjective, horns couple the sound wave from driver-to-room with a sense of transient snap in the sound wave. The leading edge of the hammer on the string on the recorded piano strikes your ears almost like is direct-wired to your ear drum. The cone/dome in contrast can sound a bit dulled in comparison, like the air damped the leading edge from speaker-to-ear.Originally Posted by JuniorJBL
Horn downsides are many so compromises abound with their use. The ideal set up is the all-horn system. This brings the speed and horn sound all across the spectrum. Since bass horns are huge, though, most of the time the first significant compromise is the use of a slow-poke cone woofer. The next significant compromise is limited bandwidth. The KlipschHorn barely covers the typical audio spectrum but does so with all kinds of colorations. Still, the magic of that speaker is the full horn sound top-to-bottom. Another pesky problem with horns is the sound return from diffraction all along the horn path. This creates nulls and peaks that are difficult to tame and color the sound to some extent. There is also time delay, power response disconnects, falling high-end response, and more, to work with in horn systems. More recent developments (and revisiting some very old ideas to be sure) with high frequency horns (yea, JBL) dispersion and wave propagation have gone along way to mitigate the legacy problems of horns.
People can become accustomed to the “horn sound” and this to them becomes the norm. Listening to direct radiators then seems wrong even though the direct radiator system is providing all of the same energy and response. Ideally, you should not be able to “hear” the horn but folks often confuse the horn effect for “better” than the direct radiator. Not necessary so, bro.
The world still needs a better horn so that leaves only the cost to worry about. And, yes, wouldn't it be nice to have the low end with the same snap and clarity heard with a horn high end? More money, much more space.
Davidf