Bookshelf speakers for near-field (desktop) use

Without a doubt & without hesitation, Burchart S400's. I have then sitting on an 88" Gladiator butcher block workbench in my audio room.. That is just about perfect for stereo imaging and no subwoofer, its not necessary. I am using Prism Sound Callia (DAC) and PS Studio M700's. Reason for that is they are 4-ohm speakers but you would not know it seeing how they are being feed 700watts i think.. There is only 1 pair of speaker terminals so obviously you cannot bi-amp or else i would.. Mads Burchart, who is owner operator of Burchart Audio in Denmark and he is quick to respond to your emails although you have to figure in the time difference. If they are out of the color or product you want he will knock some off for the wait.. I am very pleased with the speakers and i ordered them without listening to them..         

@mrdon 

How far away do you sit from your S400's? Mine would be fairly close to me, in a 9' x 8' office. I am definitely intrigued though and would power it with either my PS Audio Sprout100 for now or my Anthem MRX510. 

These have a 10” square footprint (big for computer/desktop use) but they’re excellent coaxial near field monitors with good bass extension

https://www.adorama.com/fafx8w.html?utm_source=rflaid913479

My 2 c.
In your situation I would go for powered speakers. Anything mentioned above is a worthy choice but since your space is confined why bother with an amp at all ? With your budget you can get some top of the line near filed powered speakers from the likes of Genelec, Neumann, Adam, Focal, Dynaudio. No worries about amp up to the task or potential upgrades, less cables, less space overall IMO better SQ. All of the ones I mentioned are common for Pro applications and there must be a reason for that. Each have their own character, they all tend to the analytic, more so the Genelec, less so the Dyns. all of them well within your budget.
Good luck ! 

@jbmac75 @stevecham intrigued by the Denton suggestion. I looked them up. Only $499 at MD which is far below my budget. Not a bad thing. Have you compared them against the LS50?