Hence, to get "sense" of live you only need to have a room that is larger than the longest wavelength of the frequencies that give you imaging. To get "sense of live" you need a room that is larger than the longest wavelength of the frequencies of the sense of space.
Just as an illustration, take a small bookshelf loudspeaker out into your garden. Make sure the nearest wall is at least 20ft away. Place them 6.5ft apart, sit 10-ft away and have a listen. Now, just listen to one of them. It can be quite a revelation. I find that I learn far more about acoustics with simple empirical experiments. Math and physics can explain to me someone else's understanding of acoustics. The empirical experiments show to me what the real world is like.