Need help with rear in-wall speaker placement.

[xrayyellowzebra]

I am renovating my family room. It is open to the kitchen with a cathedral ceiling. The dimensions are 20'x12'x8.5' (lxwxh). The highest point is 9.5'. My couch will be right at the back of the family room. My problem is that only one side of the rear wall exists (about 4' in). Because of the cathedral ceiling there is an upper wall in the shape of a triangle with dimensions 12'x1' (basexheight). I am planning on paradigm studio 20's for the front, cc-570 for the centre and a pw-2100 for the subwoofer. I was planning on using adp-470's for surrounds but my local paradigm dealer said that this would not work since one side of the family room has no rear wall. He told me that I should probably go with in-wall speakers (sa-30). I kind of like this idea since my family room isn't that big. I was wondering if you guys or girls had any advice on how to place the speakers (both rear and surrounds). Is it possible for me to have a 7.1 set-up or should I just stick to a 5.1 set-up? I would post a picture but I have no idea how to. Thanks in advance.

 

[jcPanny]

Surround speaker position

Is sounds like the only way to get surround speakers on the sides of the listening position would be to use speaker stands.

If this is not on option, then bookshelf or inwall speakers on the back wall are a good compromise. Try to mount them on the rear wall closer to the corners and aimed at the listening position. A pair of the Reference or Monitor series bookshelf speakers would probably perfrom better then a comparibly priced in-wall speaker if brackets are an option.