What is the best USED Speaker Under $10,000

The Ultima 2 series trades off air for linearity in the mids. You can see on the off axis graphs the output above 8.5KHz drops off sharply past 15 degrees.

Don’t most speakers drop hi frequency when measured off axis? I thought that the Revels actually do this a little less than most due to their waveguide on the tweeter...

I think Kef Uniq drivers are pretty even out to 30 deg off axis. Revel does work at making the off axis as linear as they can since the data shows first reflections play a significant role in what we hear and like. The speakers don't lack mid range energy from my listening chair. 

There are 2 ProAc D48 on audiogon for much less than $10k. Amazing speakers, to say the least, from experience!

I got to listen to a pair of kanta 3's at the store and first impressions are very good. Dynamic and detailed with bass that favors 70's rock. My couple of reservations are how far out in the room they were placed, 8' from the front and at least 10' from the sides with a 7' listening triangle. My other concern, and it was only a half hour demo after work, was the woofers output... It was exciting to listen to but I got the feeling the drivers were at on the edge without going over it. Definitely worth another listen and possibly my new favorite speaker new or used in this price range.