Non-environment. I'll have to take your word for it.
On second thought, Ethan mentions in his book that you can't get a perfectly linear response in a small room. Maybe because you can't physically put enough absorption in it. That means that you can't create a non-environment in a small room. You can try, of course, but I think we can agree that most home, project, and hobby studio owners aren't going to go anywhere near that level of treatment.