IME, soundstage reproduction is largely dependent on both the speakers’ power response uniformity and the room’s effect on it. Early reflections can muddle the best speakers’ and lack thereof can make lesser ones seem better. Some speakers will give better results in particular situations than others depending on the size shape and their placement in the room. You can get a near ideal objective performer like Revel F228 Be ($11K) but you still need to avoid early reflections, create the proper symmetrical triangle for the sweet seat, etc. A good preamp helps too.
