Is a 12' X 16' room big enough for stereo?

you guys are killin' me here! MY listening room is only 8' x 12". Try and work with THAT!!!!!!!!!!!!!!!!!!!!!!!

Have you thought about sky lights at all? Nothing like taking in the moon while listening to good music:~)

I used a pair of Hales Revelation Twos in a room about 10x11 last year. At low volume, it sounded gooda and surely would have sounded better with wall treatment. You are OK. I think your Thiels will sound fine. Maybe a little wall treatment & some bass traps in the corners will help.

My room is just over 12' x 18' x 8'. My 3-way speakers are Aerial 10Ts and I also have a Triad Platinum subwoofer to reproduce the lowest octave or two. The speaker fronts are just over 5 ft. out from the back wall at one long end of the room and woofer centers are about 3 ft from either side wall.

Soundstaging is quite nice and overall the sound is fantastic. I've had much lesser equipment in this room in the past and it still sounded quite good.

Some to many will tell you that a room's acoustics is about 80% of the quality of the sound you hear. I believe that is quite true. All walls of the room are real wormwood paneling with tongue and groove joinery and recesses about every 6 inches. The ceiling has 3 beams going left to right (from staring at the speakers) and the floor is wall to wall berber carpeting with thick padding with wooden floor joists and a crawl space under that part of the house.

Also, there is a fireplace and very few windows with built-in bookcases behind either speaker. Luck of the draw it is a wonderfully acoustic room. Not too live nor too dead.

I would make certain that most/all reflective sounds can be absorbed/deflected or minimized and speaker quality and placement will be critical as it always should be.

I'd also second the opinion for a higher ceiling. Plus the extra headroom makes you feel less confined thereby improving your ability to relax.