Absorbtion or Diffusion with dipolar speakers???

I want to maximize my dedicated listening room, and am wondering what the bets type of "treatment" should be used primarily BEHIND my Innersound Eros speakers??

Thanks to any & all!!
3 suggestions: 1. Buy 2 pairs of bi-fold louvered doors from Home Depot. Place a door, folded enough to stand up, behind each speaker. This is said to do wonders in diffusing the back wave. 2. An Argent Room Lens behind each speaker works wonders. Homemade Room Lenses work just as well and cost very little to make. "Swim Noodles" from Walmart also are said to work well. For tons of info, with pictures, on 2 & 3, go to Audioasylum.com Good luck from one 'stat listener to another. Don
Thanks Elgordo.
I tried both behind my Quad ESL 63's and opted for absorption, though I'm a big diffusion fan in general. It's great for front and back walls but not for behind dipolar speakers, in my experience. I didn't get good results with an Argent Room Lens clone behind my Quads, but the shape mismatch may account for that: tall and slender versus short and more or less square.
My experience with all types of Dipole's and Bipolar's in general, is that diffusion generally works best behind the speakers! The speakers were mostly designed for you to hear "the back wave" of the speaker's sound propegation, and absorbing usually yields a more "life-less" sound!...effectively the opposite of what the bi-pole/di-pole is trying to give you!
Each room may varry a bit, depending on other acoustical factors. But I've tinkered extensively with acoustics with bi-pole/di-pole speakers and acoustics together, and I just tend go the "diffusion" route!
One thing that could help here, is to have dipole's set up out in the room a bit more!(still should yield good frequency response however, as a priority). If you can do this, the time in which you hear the "back wave" from the rear wave of the speaker should be delayed quite a bit in proportion to the first wave that hits your ear from the front drivers of the speakers, proportionately!...limiting immage blurring(designs will varry). This will cause less immage smearing where little or no acoustic treatment is used. But you have to, like with anything, experiment.
good luck
Thanks guys!!

All GREAT ideas/responses!

What if you are able to get between 6 - 8 feet "behind" the speaker? Still need diffusion, or, is the signal then "delayed" enough that nothing is necessary??

Denf, I have my electrostatics pulled out about 6 feet from the back wall and still prefer diffusion treatment even at that distance. I use a knock off of the original RPG. Mine are buried in the wall with an acoustically transparent cloth cover so they are not visible.

I also use four tube traps, great for tuning out the bass bump from dumping high SPL into the corners. If you want to see the RPG treatment before it was covered, click on "system" link in my post. Good luck with your project.