Best high-efficiency speaker under 10K

Far superior to the Beauhorns are the Horning Hybrid speakers from Denmark which also use the Lowther drivers. The Hornings are some of the best commercial speakers out there at present, especially for ensemble jazz and vocals. If you want your favorite mezzo-soprano to bring you to your knees, you want a Lowther, but you will also want a tweeter and some credible bass...Get down to NYC and visit High Water Sound. If you have a huge room, get the huge Hornings, for small rooms the Aristotle model is within your stated budget and will blow away the other speakers you mentioned in the presence and "passion" departments...

I was on a similar quest and went to RMAF to listen to some of the choices. The 2 best I heard were the Devore Gibbon 9, I did'nt find them soft at all. They do'nt look exciting, but a lovely neutral, musical sound, I could have listened to forever.
In the end, the Devores were pipped by Daedalus Da-Ra Mas, a better sound in that it was quicker, more dynamic and excellent value at the direct from the manufacturer price. Lou the manufacturer is great to deal with too.
I agree with Newbie about the Silverline Bolero. I really enjoyed liastening to them at RMAF. I just think they have got a bit expensive, in the latest version.

I have owned the following (love the high sensitivity speakers)
Beauhorn, Lamhorn, Exemplar horn, Tonian TLM (original model), KCS Seas Exotic, and currently use the Tonian Classic 12.1s.
I have listened extensively to several Horning models (Alkabiades, Agathon Ultimates) as well as the Gibbon 9's and silverbacks and the Living Voice Avatar OBX

All these speakers, and several of the other mentioned, have great qualities.
I love the Hornings but find they like to be played a bit louder than some of the others to really gel but boy are they nice.
I prefered the lamhorn with the AER driver to the Beauhorn with the Lowther in my systems (used severl different amp preamp combos...mostly all SET 45,2A3, 300b, 845 based) but both are very good

The KCS are great and definately a value winner....I had the ones with the original single SEAS driver but see that John now has a version using the RAAL ribbon...I bet these are great

For me, I love the Tonian's with the modified Raven ribbon and Phy drivers....just a great, musical take your mind off anything high-fi speaker...seem to me, in my system, to be less overall compromised than any other I have had or heard.

I run mine with a Berning ZH230 (the new one) and have what I think is the best sound I have gotten in my room.

I think you would do well with any of these speakers if you really pay attention to your own preferences, put them into the right system and then just enjoy the effortless, musical sound such transducers are able to convey.

Coincident!

Legacy HD, or some used Legacy Whispers.