Hi Whipdancer,
I may be getting a little anal about this, but it's my modest program to correct a common misunderstanding. Surround speakers are intended to be placed at the sides of the listening area, not on the rear walls. That's the Dolby Labs specification--at the sides, up to 20 degrees forward or to the rear of an imaginary line across the listening area. That is where they work best at creating a sense of envelopment in the soundfield. QS surrounds are very forgiving of placement eccentricities and they'll work at the rear, but side placement tends to be superior.
The "back" speaker(s) in a 6.1 or 7.1 setup is intended to go on the rear wall.
There's no significant difference that I've ever detected--in terms of audible differences--between using a DVD player as a CD playback device and a dedicated CD player. Sometimes DVD players are slower recognizing and cueing up a CD, but there isn't any audible difference, nor should there be. Most such "differences" in audio quality are based on casual, anecdotal uncontrolled comparisons. If you do comparisons in a controlled, scientific manner, with duplicate CDs running in sync on the two machines you're comparing, equalized playback levels, and blind switching, alleged differences disappear.
Regards,
QS surrounds
