has anyone had any sucess making acoustic panels mainly absorbers or maybe diffusors? What materials did you guys use? What would you recomend? How thick do absorbers need to be? Oh and I am wondering if I still need absorbers on the side walls, the side walls are bare at the moment but the entire room is carpeted and there is a pretty puffy fabric coach and chair. I am at risk of deadening the room too much if I put absorbers on the back and side walls, maybe even the front wall.