'Short' horns

I rarely see anything related to this subject but want to know the experiences and opinions of those who have used either speakers that utilize short horns, or the experience of anyone who has attached them to an existing speaker. I enjoy experimentation with just about anything audio, so these are on my list.
Many tweeters are designed around a short horn, often referred to as a flare, but the size, width, length, taper, shape, you know, all have to do with the design.
How short is short?? :)

And instead of adding.... maybe build a kit? Lots of kits with everything from waveguides to deep horns out there.

The benefit of a horn, besides efficiency, is dispersion control, this can really improve clarity at the listener location.
Mr. D,/ Erik,

Yes, it is true that design must be involved for the proper flare for a given driver, and because of that, I am stabbing in the dark at best.
What eluded to this thought was in reading part of the ’Getting Better Sound’ by Jim Smith. I do not agree with every thought that Jim has, yet, there is inspiration here and there. In this case, he mentions the directivity of some driver designs (horns, I bet) that encourage less reflections from side walls and other room boundaries. I had an old set of such horns lying around that I have experimented with years ago. Even though there isn’t perfection to be had, the application has one desirable effect. The dispersion of the drivers is more spot on, and maybe even to some degree matches better the sound of the drivers rear loaded horn design to begin with. When the novelty wears off, I may well have other things to conclude.
 Erik, likely I will be encouraged to look into kits as well in the future. These short horns are maybe 2 1/2" deep with a fast flare after the first 1 1/2". They are the diameter of the cone area which is 5 1/2". I will try to seal around the edges since I am sure it would have a different effect.
There's a really neat, short, oval horn design out there I've seen become popular in home kits, do check them out.

  Thanks again. Yes, no doubt there is a mountain of horn designs as well as many others. I have been fascinated by speakers for decades going back to my early youth. The first speakers that I ever built in '76 were a knock off of the K horns. I built them in high school shop. The bass is still unforgettable to me, but the midrange is where things didn't add up as well. The tweeter used was the K77? Sounded fine. Anyway, it has just gone from there and has been a great experience.
So glad you've had so much fun, and that's what this is about, when it isn't about education and culture. :)
 I was born with 'what if' in my head. That can be good or bad, but the side of curiosity led to can this be done better? Often times the answer ended up being just more experience under my belt. Then there are those times that something really shouldn't work, or at least work as well as it does. 
 The target relies on a bullseye to make shift the rifle. The eye tells us the score, and that is enough for that approach. Perhaps I am attempting to shoot over the shoulder while using a mirror. More than that, I am not even aiming at the same target as most others. Could be that after I fire, a theory falls.
I do quite a bit of DIY.  Right now I’m listening to a pair of 2 way speakers with a 6.5” woofer and a 3” wide-range driver mounted in an 11” diameter turned maple horn.  Design is similar to the Viking Acoustics Berlin.  To my ears, the sound is quite good with excellent depth and imaging.  I also designed a pair of LeCleach style horns for the same driver that I’m waiting to get back from the finisher- they’re quite amazing to listen to and sound far better than just mounting the driver to the cabinet baffle. Both styles are fairly shallow.
 Man, I just checked out the Viking website. This is very impressive woodworking! Not manufactured, but handcrafted. Simply beautiful. I was no master at the lathe, but this does give inspiration to the idea. Thanks for the reference.
Also, look at the Cessaro Wagner l- that’s a pretty good example of a LeCleach horn at the top.  It’s smaller- I had a woodturner here in Chicago turn a pair for me, with a full range driver from around 700 Hz to 20 kHz the sound is pretty stunning.  One of the things I noticed with a shallower design is there’s less “shout” than is sometimes typical of horns with more depth.
  The midrange shout of many single driver designs is especially harsh for me to listen to. I absolutely agree with the danger of this being the outcome should the wrong taper, driver choice, or other mistake is made. 
 I also agree that the presentation from some kind of lucky selection of each component can yield no less than amazing results. More than anything it seems to come from the dispersion and volume in balance with one another. Get it to your ears before any trouble starts, HA!