Optimal speaker size for given room, or drivers?


How do I determine what speaker size to buy and how many drivers are appropriate for my room? My room is 14x22, with an opening at the back into a hallway. I also have another 6x8 foot arm toward the front. Ceilings are an average of 9 feet tall. Listening position will be 13 feet from the front, speakers 4 feet from the wall and 8 to 9 feet from each other. I can't try any of these at home without committing to a purchase.

Considering a full range like the B&W 802d, Thiel 3.7, Tyler Decade D1 or D2, or Sonus Faber Cremona M. These are examples of the size I am looking at, not speakers I have settled into (I have only heard the 803s, Cremona and older 3.6, for example). Something not too big (150lbs or so) and full, but not overwhelming. This isn't a long-term house for us and although a larger speaker would sound fine in this room, I may be using them in a smaller room in the future.

Some of these speakers feature many drivers and midranges, such as the Tyler D1, whereas others such as the 802D are essentially 1 midrange and 1 driver. The Cremona M is somewhere in the middle. What are advantages and disadvantages to each type of design? Is a larger array more complicated and harder to pull off, or is it simply a matter of cost of manufacture?
komaki
I second the Quatro's my dad owns the wood signature model and his room is close enough in size to be comparable and while nobody can predict how any given speaker will perform the Vandy can be tuned to sound great in most any application.......that I can say for sure.
Vandersteens are as dark as whats around them from Pre, to Amps, cables and source, they are a pretty honest speaker with a touch of warmth that is rarely called a negative.
Find a dealer that will let you bring them home....

All of the speaker you listed should be ok ( some better than others). A word of caution about the 802Ds. They need a lot of space to sound ballanced. They tend to be a little boomy and they can get very boomy in small rooms. Now in the right room with the right gear they can sound great.
Vandersteens will likely be smoother and no doubt much less problematic with bass in room adjustability.