You have to give a listen to the Sonus Faber Grand Pianos. They absolutely disappear and hit all of your requirements except price. They are actully less than you are looking to spend. If you are looking to buy used, you should listen to the more expensive speakers they make as well. They are phenominal.
Which Speaker in the 4-6K Range?
I am interested in buying a pair of full range floor standing speakers that have the following attributes:(1)Sensitivity of 90db or greater. (2)Bass extension down to at least 25-30hz. (3) Solid built quality. (4) Ability to simply diappear and (5) cost about 4-6k. I am considering the Silverline audio Sonata and Coincident Technologies. I prefer the Hales Design Group Trancendence 8 but it costs 10k unfortunately. Please help.