Mt10425,
From my own personal experience, I would stay with 7.1 as I found 5.1 to be far less satisfying for surround envelopment.
If you can experiment with speaker positioning, I would suggest two things. First is to move the side speakers forward so they are 12' from the front wall, same distance as the seating. That will provide a side source. Second, I would move the rear speakers out of the corners, still along the back wall, but moving each one in about 2' - 3' from the side wall.
My other thought is to look at the processing that your PrePro provides. Since there are no 7.1 sources AFAIK, the surround processing is important. I could not find the 317 listed on the B&K web page, so I don't know what processing it offers. I concur with the above recommendation to try Logic 7, which is what I use to great effect. Alternatively, you could try DPLIIx. Both can generate 7.1 outputs from any source.
Thanks
Bruce
From my own personal experience, I would stay with 7.1 as I found 5.1 to be far less satisfying for surround envelopment.
If you can experiment with speaker positioning, I would suggest two things. First is to move the side speakers forward so they are 12' from the front wall, same distance as the seating. That will provide a side source. Second, I would move the rear speakers out of the corners, still along the back wall, but moving each one in about 2' - 3' from the side wall.
My other thought is to look at the processing that your PrePro provides. Since there are no 7.1 sources AFAIK, the surround processing is important. I could not find the 317 listed on the B&K web page, so I don't know what processing it offers. I concur with the above recommendation to try Logic 7, which is what I use to great effect. Alternatively, you could try DPLIIx. Both can generate 7.1 outputs from any source.
Thanks
Bruce