Bookshelf speakers for small room

Sorry about that..for bookshelf speakers no one comes close to musically right sounding speakers like Fritz !!!

I have the NAD M33 along with Monitor Audio Gold 100 bookshelf speakers.  Love, Love, Love this setup!  I too, have it in a smallish bedroom, you can see my setup in my gallery.  My room is treated, too.

I’ll just throw out a combo of a DENAFRIPS Venus ll DAC, Raven Audio Blackhawk ll tube integrated, and Joseph Audio Prism or Pulsar speakers. 

BTW, you might also consider Hifiman Arya headphones as they may come closest to matching your HD800’s soundstaging but with detailed yet natural sounding highs.  FWIW, and best of luck on both endeavors. 

@labelman @goldprintaudio 
Goldprintaudio mentioned the Rega P6, which I have and love. You can go down one step to the P3 and have more money for a better DAC, really depends on what do you listen more, and more closely to, records or digital. Many other good suggestions above. 

Regarding your Sennheiser HD800S, I would start by trying a tube headphone amp. The Atom itself is not exactly the bees’ knees as a source. You know the story: trash in, trash out. If anything the Senns are very transparent and tell you that your source and amp are not up to scratch. If you are not ready to invest in the above I would just consider a lesser headphone - HD650 from the same company for instance. 
Expensive, but you can find them much cheaper ex demo, the WA TuneTots are still my go to for small rooms, boundaries etc. Raidho also perform splendidly near field but they also cost top dollars.