Absorb or Diffuse Behind Listening Position?


Hey All. Starting to finally treat my listening room. My listening position is up against the rear wall (head probably being spaced about 12" from the wall when sitting down). I’m putting 2’x4’x2" absorbing panels behind the speakers, but what should I choose for behind the listening position? Diffusion or absorption?

There are al lot of windows in the room, with horizontal louvered shades which act as pretty decent diffusion; and a big built-in bookshelf on one side wall also helping with diffusion. On either side of the wall behind the listening position are a pair of glass French doors, untreated at this point, and the room sounds a lot better when they are left open to the big room on the other side of the wall. I haven’t tackled the ceiling yet either. Thanks!
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Hello,

i'm seating near the rear wall. i don't have other option really. My ears are about 30cm from the back wall. So i read here some comment's about using an absorver panel (fiberglass) so i went for that but...after i put the panel in the back wall the voices turn out flat instantly, so that is no solution.
Any ideas please?
Thank You
In fact it could be either one dependent upon the rest of the room.
From the description absorption is needed on the side walls when it is possible to fit a panel in.
Start at the front end of the room then experiment at the back wall for the type that works. Do keep the listening position away from the wall.
Again it depends on how the room sounds at this position.
Definitely use the French Doors to adjust the balance as well.
I would absorb the back wall behind the listening position, you're sitting too close for diffusion to work properly. Bass trap corners if you're in a dedicated room and diffuse everywhere else especially first reflection. It's trial and error and no two rooms are exactly the same so you just got to experiment. Listening preference differs also. Good luck on your journey!
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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.