I want to jump in and help out, but the rest of the gang has it covered.

The only thing I'll add is that you should get it as close to symetric as you can. What you hear is the sum of the direct and reflected sounds and a non-symetric layout can affect that openness or airy sound.

Fred

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Blujays1: Spending Fred's money one bottle at a time, no two... Oh crap!