Can you maybe explain a bit clearer what the setup will be? If you mean on the rear wall behind your couch, that is where I have mine due to limited options. The QS8's should sound great just about wherever you put them.

I mounted mine about 2-3 feet above my listening position, and spread apart a decent amount (at work now, don't know the exact distance), about equidistant from my listening postion. I used the Axiom provided brackets, and everything looks and works great.