I would select full range floorstanding loudspeakers with a frequency response rated as close to 30 Hz to 20,000 Hz +/- 3 dB as possible. And of course listen to them with music material you like as much as possible before you buy.

As I stated in another thread, you will likely need room treatments for good sound in that room. Hings Soundproof and Vibrationproof Products, 289 Reclamation Street, Mongkok, Kowloon, Hong Kong, 757 2533 2788. http://www.ethanwiner.com/acoustics.html

You might be able to listen to Vandersteen 2Ce Signatures IIs at:
The Sound Chamber
Chekiang 1st Bank Ctre
1 Duddell St. Unit 1801
2 810 0233

Hello Worf, do you have a budget you can share with us for your speakers please?

Your room is about the same as mine; that is a fairly large room.

There are very few "full-range" loudspeakers for under $10,000 that will even begin to supply enough clean bass in that room. I would think that the B&W speakers or dozens of other high-quality small speakers would be fine (such as the Opera Mezza or Sequerra Metronome 7.7 or EPOS M16i), and then add two good-quality subwoofers such as the Velodyne SPL-1000R or SPL-1500R or the Vandersteen 2WQ, or a pair of the Thiels, depending on your budget.

The small main speakers will probably cost you between $500 and $2000, in most cases, and the 2 subs will cost from $1500 to $8000 (yes, you WILL need two subwoofers for a room that big).

The small speakers will handle everything down to 70 HZ, and the subs will do the rest.