Room treatments behind or between speakers?

If your room is small, you will most likely get a reflection off the back wall behind you, which then bounces off the front wall and then back to you. I would think absorption on the front wall between your speakers and maybe try some diffusion on the back wall behind you. You could try that and also reversing the combination to see which works best.

I have no treatment on my front wall since my 31 foot long room is a long enough distance that the rear to front wall and back to me reflection isn't an issue. I've been told that at that distance the time delay of that reflected sound is great enough to become a non issue.

Tboooe,
You are welcome.
If your rear is open to the family room, then reflections on the wall behind your speakers should not be as big a concern as it was in my case. You probably also want to think of speaker re-positioning or nearfield listening.

Ghousthouse,
I know what discussion you are talking about. That discussion was based on the Floyd Toole's book - "Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms".
So, a lot depends on the room. What worked for me, might not work for others. I purchased the panels and played with the positioning. That is how I arrived at the current setup. When I started this system, I used to have a tube TV between the speakers. That was the worst setup. Someone suggested a blanket on the TV. It was a big improvement in imaging. Further reading indicated that anything flat and smooth between speakers is horrendous for the sound. With my current setup, there is nothing really flat. Sound breaks up on the equipment stand and gets absorbed because of the panel. I am pretty happy with the setup.
I am thinking of moving my equipment to the basement downstairs after re-doing an area specifically for this hobby.

Tboooe are you still in OC ?

Nothing between the speakers? I don't think so. It should not be your components, including a TV. Some years ago I added a free standing Furtech Room Diffuser to fill the void. Does wonders. Plenty of stuff on the net about that product. Behind the speakers? Depends, its complicated. With out knowing how your speakers are 'ported', if at all, can't provide advice.

Samhar...yes I am still behind the Orange Curtain in south OC.