Recommendation for Good Quality Desktop Speakers

The New Proac Tablette 10 is very tube friendly
  offers an ideal 10 ohm load, are sealed for close wall placement, and sound incredible with many decent amps.
 Best,
  JohnnyR
 Proac Dealer 
http://www.tonepublications.com/review/the-pro-ac-tablette-10/

Silverline Minuette Supreme are very compact and musical. The Kef LS50 is very detailed and forward...if you are like me, this would sound great at first, but eventually fatigue you.  

I've been using for several years the JohnBlue JB3 single driver speakers in a similar setup with a 10 watt El84 tube amp. Obviously, if deep bass extension is important to you this isn't the gear you'd want but for near-field listening it's very satisfying.

just very slightly larger, but my favorites have been Quad 12L2

Hi -- I am thrilled by the desktop speakers I have been using for about three years. They are Audience Clairaudient "The One" speakers, and are only about 7" high x 7" deep x 5.5" width. They are single drivers so throw a great soundstage at a short distance.

The are not incredibly efficient at 84 dB, but will be easily driven by your amp at late-night listening volumes.

Clairaudient also has upgraded versions with the V2 designation. And it makes the slightly larger 1+1 desktop speaker that is many an audiophile reviewers’ desktop/mini speaker reference. Both have won several awards. 

I find them truly small enough to be a desktop or bookshelf speaker with excellent dynamics and a non-fatiguing sound. Worth a no-risk audition.