As others have said, binary amplitude diffusion on the back wall would be a good solution for you. From reading about them, it's less important how far away from them you are, as compared with say quadratic diffusion. And you do get a nice balance of both absorption and diffusion with than technology.
I have a little more space, and I'm personally looking at building some folded well (FWD) diffusers, they fold the wells that are longer at 90deg behind shorter wells. In conjunction with this I want to try the fractal diffuser well plates.
It uses a scaled down diffuser as the face of the bottom or back of the wells, simply put, if you DIY your quadratic diffusers, cut scaled down diffusers as the end of the well.
At less than 4" they won't protrude much into the room, and will cover a broad range of higher frequency diffusion as well.
Please keep us posted, it's good to share these experiences, as room treatment isn't highly prolific as far as threads go on the Gon.
I have a little more space, and I'm personally looking at building some folded well (FWD) diffusers, they fold the wells that are longer at 90deg behind shorter wells. In conjunction with this I want to try the fractal diffuser well plates.
It uses a scaled down diffuser as the face of the bottom or back of the wells, simply put, if you DIY your quadratic diffusers, cut scaled down diffusers as the end of the well.
At less than 4" they won't protrude much into the room, and will cover a broad range of higher frequency diffusion as well.
Please keep us posted, it's good to share these experiences, as room treatment isn't highly prolific as far as threads go on the Gon.