Best speaker 3k to 4k used?

What do you think is the best speaker in the 3k to 4k range(used)? I am using solid state electronics(Gryphon S100 & Tabu preamp). Room size is 14' x 20'.
I just bought a pair of how demo Silverline La Folias direct from Silverline at a very substantial discount but there's also a pair listed here for $4000 OBO. I haven't received mine yet but a brief listen at the show in the Spring and the great reviews at have me convinced that these are terrific speakers for the money at the $8000 list -- let alone at less than half that amount. They could be a bit too much speaker for your room, though.
You might cruise over to Greybeard Audio's site:

Greybeards are superb quality, and will provide very natural, fatigue-free sound. They are having a sale of their inventory because the designer, Tim Wright, has a serious health condition. So you can get a killer deal on the speaker of your choice - they come with free shipping and a 90-day warranty (which would easily cover any manufacturing or driver defects, though I very seriously doubt Greybeards would have either).

The Greybeards are among the most musical speakers I heard at CES 2001 and 2002, and among the most un-boxy sounding (I own and sell full range electrostats, so I'm pretty intolerant of boxiness). Superb midrange, very solid bottom end, and if anything maybe a wee tiny bit laid-back in the very top end. This keeps them from sounding edgy with mediocre recordings.

I have absolutely no financial interest in Greybeard.

Never heard this combination but why not consider Martin Logan? They sound quite good with Krells,may do even better with Gryphons.The choice of dynamic speakers is endless.Just make sure to keep your S100/Tabu combo,no speakers in this price range are worth replacing them.
Try soliloquy 6.5. Agree with the Martin Logan suggestion as well. Avoid speakers from companies going out of business. Also Silverline does not extend warranty to second owner, had bad experience with the finish and no viable recourse. Best bet is to get warranty coverage.
For $2500-2700, you can get a pair of Vandersteen 3A Signatures, which compete very well against speakers costing twice their MSRP ($3500). Before you make a purchase, you would be well served to audition the 3A Sig's.
I would think you'd be hard pressed to find a better used speaker than the Aerial 10T. Sonics, appearance, and fit'n finish are second to none for anything near the price range you mention.

However, a high-powered amp is pretty much a requirement for the 10T. I'm now on my forth or fifth amp in the last two years and I am more than impressed with the full range sonics of the 10T.

Von Schweikert VR 4.5's
Apogee Diva!!
I too would recommend the Aerial 10T, which I believe continues to be one of the best buys available and pretty easy to find in the upper end of your price range in excellent condition. Unless you have a very large room you do not need a high powered amp to enjoy these speakers, but the minimum recommendation is generally 100 watts per channel. I used a single BEL 1001 MK3A, which is 50 watts per channel for a year or more and was very satisfied considering I traded up from a Classe CA300. Today I use two of the BELs bridged mono (200 watts)in a 13X22 room and that is all the power they need in a room of that size.
What kind of music are you listening to the most?
Thanks for the suggestions so far. I need a versital speaker because I listen to a variety of music. I like female vocals, accoustic, jazz, light classical,and some rock.
Von Schweikert VR4.5's as stated by 'Acuujim'.
You should be able to get into a pair of these second-hand for about $2500. Then start saving to have them sent off to Von Schweikert for their new upgrade, which is about another $2200.
The upgrade will turn these speakers into something out of this World,...they are already a great speaker though!
Dynaudio Contour 3.3 or Silverline La Folia. Dynaudio probably has better integration, but Silverline will go deeper and probably has better midrange.
Third recommendation for Aerials - for your amp and listening tastes the model 6's would be perfect (yes, I use them too..). I use a 100 w/ch Rowland integrated - the combination is fantastic. I use them even in a decent sized room (21 X 13) and only need to turn on my REL Storm for heavy classical/organ music. Try to find a similar 3-way speaker (the key word, 3-way), with trickle down technology (same tweeter as 10t) and this level of build quality, for the price of the model 6. I have yet to hear a speaker under 5k that sounds better overall... It certainly is one of the best values (used) in high end...
A pair of Gershman Acoustics Avant Garde RX-20 (demoed or used). Read rave reviews in the press.