Imaging/Soundstaging - Does room size matter?

Hi guys,

I have a great little system in a pretty small room, 17 x 13 x 10. The center image is perfect. On vocals, the speakers totally dissappear, and all I hear is the singer chillin' in between the two channels. But most things that aren't supposed to be completely centered don't image very well. Instead of simply coming from one side or the other, they always seem to come directly from the drivers. Is there something that room acoustics or speaker position can do about that, or is it just going to be that way because of the size of the room?

Thanks!