I've always looked at listening to good stereo recordings thru ANY surround processing mode as a gimic more than anything else. Heck I value DVD-A and SACD for their greater dynamic range in 2 channel than I do for surround. Soundhound is right on as to a pure unaltered signal - get a Passive preamp.
Lastly I'm sure there are Preamps above and beyond the 950s capabilities(did ya ever read thru the Absolute Sound?!) But a preamp at 950 paired with a 7100 0r better is a great buy!