Acoustic panels

I made four acoustic panels (29" x 16" each) out of some extra dynamat, and 1/2" MDF. My problem is that I really have no idea where to stick 'em, especially in regards to height. The room is is 11x12x8, and the highs are brighter than bright; three songs and i'm down for the count. I would appreciate any advice, theory, whatever. The speakers are hales rev twos.
I'd suggest reading "Sound Studio Construction on a Budget" by F. Alton Everest. He covers domestic listening rooms too and this book came 10 years after his "Master Handbook of Acoustics", and has info on newer products--RPG, especially. You can learn all kinds of things about room acoustics from this book, and where to locate your four absorptive panels in particular. You'll probably want to do other things too.
i'm sure you'll wanna read something on the subject but i'd say, generally, (if your sound panel design works-i have doubts) you'll do best starting directly behind your speakers, assuming you've already removed EVERTHING from between your transducers. go toward the side walls as far as possible, covering the area in the very center first..
You want to treat all first refelction points. Usually, this will mean 2 panels on each side wall, two panels on the ceiling and, depending on hwere speakers ar eplaced, 2-3 panels on wall behind the speakers. For the final touch, one panel to diffuse sound behind the listening position. If you only have 4 panels, suggest you treat the side walls. To gifure out where to place them, have a friend move a mirror along the wall while you seat on the sweet spot. You want to treat the spot on the wall where you see the tweeter from each loudspeaker reflected. If the panels are large and the speakers close to one another, one panel may do the trick. If you must know more, the book by F. A. Everest is a good place to go. R. Harley also deals with this in his book.
Thank you
whats dynamat?
Dynamat is an acoustic treatment that is used primarily in car audio. It is a flexible sheet that can to be cut to fit door panels, hoods, etc..
Dynamat is available (in several variations) from Parts Express
You will have to cover the entire room. But i am not sure, how effective it will be??!! Because you cannot expect a good result from homemade panels. Better you should try ready made panels. Now-a-days different types of very good looking panels are available in the market. You can visit  to have an idea of different type of panels. Thanks.
I had serious problems with piercing upper midrange glare in an untreated room with my Focal 936's. A doubt Dynamat is better than rubber backed carpet which was my first solution. It was inadequate. I resorted to 12"X12"X2" acoustic foam panels. 36 sq/ft spread across the wall behind my chair. That stuff got the job done well for about $50 on Amazon. 
Dynamat, if I'm thinking of the right stuff, is designed to keep large areas of sheet metal from resonating. I don't think it'll serve your needs well. You definitely want to kill those first reflection surfaces and I'd start with the biggest one right behind you. Diffusion is a useful tool as well, and if you have the tools and facilities to make some diffusers you may want to try that. They're useful for softening the sound rather than just sucking it out of the space. Diffusers are especially useful behind and between the speakers assuming the speakers themselves are well balanced. 
Thread is 17 years old. OP probably found a solution by now ;)
Lol... good catch..