We are in the proccess of building our dedicated 13x22 home theater. We have 2 rows of seating with about 3 feet to the side walls and 5 feet from the back wall. Is this room big enough for 7.1 or should we do 5.1. We are using Def. Tech. Mythos STs for the mains, Mythos ten for the Center, and Gem XLs for surrounds. We are using an epson 9700 and a 120" screen. If the Mythos STs and the ten were behind velvet curtains would it affect the sound much? Thanks for any help.