My question mostly relates to 2 channel music. I understand that 5.1 or 7.1 channel movies (or SACD and DVD-A) have a center channel, and the center speaker would simply play the center channel (and it's mostly voices/dialogue, right?).
But what happens on 2 channel music when you have your receiver set to 3.1 (or 5.1 w/o the rears)? Does the receiver mix the left and right channel equally into the center speaker? How does that affect sound quality on music? If it just mixes into the center speaker I'm wondering if that just muddies up the sound.
And/or should the center speaker not be used on music but only for movies?