Would someone mind explaining this to me? What is the difference between music mode and movie mode? Is this a processed two-channel to seven(five) channel? I use the seven-channel stereo option on my Denon AVR which I use as my pre/pro for now and it's pretty nice. Is Dolby PLIIx a more "accurate" presentation?

Gonk has a nice write up on the different DSP types in his Terms and Technology section here it has a link to a Secrets article comparing it to the older types.

Seven-channel stereo simply copies the left and right channels to all left or right speakers. It is quite different from Pro Logic II and IIx. The link that mm_half3 offered is a good place to start.

Thanks for the info fellas.
DL

The biggest difference is that the Music mode has adjustable parameters, so that you can customize the surround processing for your particular tastes (make it as subtle or dramatic as you want). The Movie mode has no adjustability.

Are those Music mode parameters user adjustable, or are they done by the design/engineer team of the device utilizing the DSP? I am not aware of any adjustable parameters on the 990 for music mode....does not mean they don't exist, there are sooooo many things to tweek with the 990, I have missed things before.

They're user adjustable - on the 990, check out the "Surround Config" menu for the dimension, center width, and panorama settings.

oooh yeah...more things to play around with...thanks Gonk. Have you tried adjusting the settings and found them useful?