I have recently moved and my listening room now is unfortunately a small box of a room of approximately 13 feet by 12 feet (with less than 9 foot ceiling). It is carpeted on the floor but the rest of the room is concrete (with some windows). I understand that this room cannot get much worse for listening, but I am stuck with it for the foreseeable future. I think I could live with the smaller (and much less focused sound stage) but I cannot deal with the mid bass boom which is making most of the Rock/Pop music unlistenable. I would greatly appreciate any recommendations that you can make on simple (and hopefully cost-effective) room treatment devices which would remedy this problem. Please excuse me if this has been discussed at length in other threads but I am new to the Forum and my search of previous threads has yielded nothing. I thank you all in advance.