[bpape]

I'd disagree slightly on the location of the columns.

Normally, the rear most columns house surround speakers and should be placed accordingly. That may be directly beside if you're using a dipole/bipole surround and only have one row. If you have more than one, then it ends up slightly behind and between the rows.

The front column would be placed where it's visually appealing and balances the room and the rear column location. If it happens to hit a reflection, that's OK IF you either have the open part low enough to catch it OR have the front wall treated so the reflected sound back to the front is absorbed. If the front is not at a reflection point, then absorbtion on the wall will suffice.

Bryan