Best high-efficiency speaker under 10K


I have never played in the high-eff speaker / low-powered amp space, but I've read so many things that I would like to give it a try. I own an EAR 859 integrated amplifier, De Paravicini's interpretation of SET. It's pretty incredible, especially if you consider its price tag. I am now in the business of choosing the right speaker. I listen to a lot of jazz and vocals and opera. So, I can do without the sub-40HZ frequency range. I would like to stay between $3K to $7K, certainly below $10K. Here are the options i am considering:

1) Zu Audio Essence.
2) Beauhorn Virtuoso (single driver)
3) KCS louspeakers (the model that uses the SEAS exotic driver)
4) Devore Gibbons 8
5) Living voice Avatar

If I had to choose right now, I'd go with the Beauhorn, but I know their limitations.

Any thoughts/personal experiences with the above or any other speakers in this range? Thanks.
ggavetti
Hello fellows, I just had a chance to listen to a pair of beauhorn that a local gentleman owns. I first listened to them with his electronics ($65K worth of equipment..a nice audio note SET power amp and a battery powered preamp whose brand I don't recall), and then with my own Lavardin IT. It's a very interesting speaker, the sound is palpable, 3-dimensional. It really looks like you're a few feet away from Ray Charles. Of course the extension is limited, especially the low frequencies and I did not like the use of REL subwoofers (after the first tune I asked him to diconnect them). The way he positioned the speakers made for a very intimate experience with the speaker or player or orchestra. it's an incredible experience but I probably like a more distant perspective, which can be had by simply repositioning the speakers a bit closer to the walls and the listening position a few feet farther away from them. By the way, these speakers used an optional supertweeter. I tried them both with and without the supertweeter. There is some difference but I am not sure which option I like best. It probably varies with music. As for my Lavardin vs. Audio Note, well, it was day and night. The AN was warmer, more textured, quieter. The Lavardin was drier, more extended, leaner. Through the AN you have the impression to almost touch the players. The Lavardin puts you a bit farther back in the audience. Both of them did very well. Which one is best is a matter of taste.
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If It were my money I would move KCS up to top position in your speaker hunt.
For the money you are wanting to shell out I think you would be hard to pressed to find better than one of JohnK's offerings from a bigger loudspeaker manufacturing concern.I have a pair of KCS Oris 150's bought as cheap as chips on here, the previous owner of my 150's I beleive had a pair of Avantgarde Trio's prior and I beleive he prefered the KCS 150's, and at a fraction of the cost new. I have personally not heard any of the Avantgarde range of speakers.
Gawdbless thanks for your suggestion. I haven't heard a single person criticize the KCS's, ever, which means they're really good. I have two extra-audio issues with them. First, I don't like their standard look (while many other speakers in this niche are prettier to my eyes). Second, I am not sure what their resale value is. From this standpoint, a more mainstream brand should be a safer bet.
I would suggest building your own, I just did it and could not be happier. There is a designer and a cabinet builder I can put you in touch with. Here is the designers site, mine are pictured through the link.

http://www.clearwaveloudspeaker.com/Symphonia/Symphonia72.html

These are my actual speakers driven easily with 30 watts.