Dipoles and sidewalls
 

In a smallish room what is best at the first reflection points for di poles?
diffraction or absorbtion :umm:

How small is "smallish?"

In general I would say the side wall first reflection points should be absorptive or diffusive--not reflective.

Billy, 2" thick absorption would be best for Logan's IMO

13X13X11 ft ceilings

Absorptive side reflection points will work well for you.

According to S. Linkwitz here : Room Acoustics in section D - Loudspeaker and listener placement

"The wall behind the speakers should be diffusive. The rear radiation from a dipole must not be absorbed or it is no longer a dipole. Similarly, the side walls should not absorb sound at the reflection points but diffuse it. A dipole can even be towed in so that the listener sees the radiation null axis in a wall reflection mirror." Some side reflections actually improve the intelligibility of sounds coming from the speakers.

I find this works well. You'll have most problems with placement relative to your front wall in a small room as planars sound best 4 feet or so away from it.

In a room that small I would recommend absorption. Perhaps something like our 242 panel. If you wanted to add a bit of diffusion to it then use something like our 4A Alpha panels.
4A Alpha Panel Diffusor / Absorber

Do you also angle you diffusion panels depending on how much you toe in your speakers or you simply keep them flat against the front wall? What is it that works best?

cheers,

david