To use software to calculate treatments requires extremely detailed measurements and a perfectly symetric, closed room. Otherwise, a detailed investigation with advanced software is needed. Just experiment to tastes. To know how to treat your room depends on what music you listen to. If its Jazz or Classical, dead rooms will sound awful. The best "generic" advice is treat all the corners with bass soakers (you'd be surprised what foam products like Aurelex will do here), treat the primary reflection points with a broadband absorber that will reduce reflections, but not soak em up all together. It is important to use a material that absorbs equally through the spectrum so you dont change the reflecting material's balance. After this, diffusive treatments ( Bookshelfs with random items in them) will give you a life like ambience, while minimizing time/phase problems and seating location nulls. As for subs, I have never seen one mounted on a platform as to equal the height of the main woofers! Just play something with a rolling bass line with the sub at your seating position, and walk around the room till you find the quietest bass response, and put the sub there. This is opposite to some advice which tells you to put it in the loudest response is, but this will give you a boomy response. Good luck, and remeber to experiment to taste, don't follow some rigidly applied rule, and don't deaden the whole place! Dead front or dead rear rooms, to me, kill the ambience.
room acoustics
I'm tearing out the panelled walls in my listening room and have the opportunity to design some acoustic treatment into the room as I refinish it. My reason for posting is to seek advice from those who have travelled this path before. The only plan I have so far is to make the amplifier/speaker wall absorptive (via several inches of insulation). I'm most concerned about the effects of the sliding-glass door and the off-center fireplace. A description of the room follows. The room is 12 by 19 feet. (speakers are on the short wall.) The leftmost 3/4 of the opposite wall is a brick fireplace. (the other quarter is the entrance to the kitchen ... no door) The left wall also contains a sliding glass door. The right wall is uninterrupted until you reach the rear of the room, where there is another passageway ... 90-degrees to the aforementioned Speakers are full-range, and the listening position will be out in the middle of the room. Any help is appreciated. David