If those walls are concrete I'm not sure you can fit enough bass trapping in there to make that spot work...
The problem is (if that room is in fact concrete) that the concrete will not let the bass out -through the wall- but traps it in the room. If there are big access doors to the room that will allow some bass out, but those 3d concrete sections of the room will remain a problem.
But if those wall are drywall, no prob. They will breath bass out a lot easier.. Then just need to control slap echos.
Hopefully the cavity depths vary in a lot of places - this will tame all kinds of different low end modes nodes and toads.
Or is at least about 10-12 inches deep - as this will basically (considering the angular access of room sound) kill basically all the bass problems.
Very nice to vary a few depths of drywall. And some slat paneling, And wood. Wood is good. What are the plans for the walls?