Ethan ,
Problem : the bass is boomy .
My room treatment : 3/4 ( 30 inches from the bottom to the ceiling ) of the wall behind the listenning position is covered with foam absorbers , some diffusors are on the ceiling and I have two bass traps (6 inches of Corning 703 )in the corners of the wall behind the speakers . My room is 15 X 16 . I have a 62 inches TV between the main speakers .And I have a lot of bass behind the TV set , should I treat with absorber or diffusor ?

I would stick with absorption with the room that size.

>My room treatment : 3/4 ( 30 inches from the bottom to the ceiling ) of the wall behind the listenning position is covered with foam absorbers<

I would move that foam to the side walls and put THICK (I like 6" panels) absorption there. It will help to control the strong low end nulls and peaks coming from the back wall area.

And you won't put anything on the bck wall , behind the TV ?????

The back wall would be behind you (well that is how us acoustic guys think of it). And no I really am not a fan of diffusion on the front wall (where the speakers are).

What do you recommend for the front wall , where there is a lot of boomy bass ?
Is there another solution than putting the foam on the side wall?Is it possible to let the foam where it is and put the panels elsewhere ?You surely know the waf :)))