There really is no right answer to this question as it depends on the home theater system you choose. All of the home theater systems in our list are 5-channels, which obviously do not offer as much power and sound amplification as a 7-channel system would. A good room size for your home theater system can be anywhere from 250–300 square feet with a height of anywhere between 8–10 feet tall. When broken down, you’re looking at a room roughly 20 feet wide and 13 feet in length. Please note that not all home theater systems should conform to these measurements and if you have a much larger room, a 5-channel system may not be the best choice for it.