Separate names with a comma.
Let me answer to you with the following quote:
The left to right placement is in the mix. The mix is designed to be heard from speakers 10 to 12 feet in front of you. The distance from the speakers to the listening position create the space for the soundstage to exist in. Moving your head allows you to perceive that distance. Is that clearer?
Sorry, but it's complete bull$hit.
Here you go... You can also try googling sound localization. http://asa.scitation.org/doi/abs/10.1121/1.4800148