The biggest impact on soundstage is speaker placement. Speakers which are placed to close to the wall will possess increased bass, but they will surrender soundstage. Moving the speakers out from the wall will benefit soundstage depth but there will be give-and-take with your bass response.
A couple of things which might be of benefit are Robert Harley's book "The Complete Guide to Highend Audio," Laura Deerborn's book "Good Sound," or you might try http://www.rivesaudio.com
All three will deals with your questions from one angle or another.
A couple of things which might be of benefit are Robert Harley's book "The Complete Guide to Highend Audio," Laura Deerborn's book "Good Sound," or you might try http://www.rivesaudio.com
All three will deals with your questions from one angle or another.