Let's Talk About LIVE ROOMS

There is a lot of information here about how to make a good control room. But I'm interested in talking about the room where the musicians go! :jammin: :jammin: :shot: :yahoo: :jammin: What makes a good live performance room for recording? I'm beginning to grasp the concepts of isolation, wall leaf construction, and spacial limitation. I'd like to open this up as a general discussion, rather than the "I have this room, $$$, and want to make it awesome for my samba band to practice in, but my neighbors complain that they can hear when I flush the toilet" thread. So how does one go about designing a magical live recording environment? What are the considerations people make when designing a performance room? Why did they make the decisions that they did? I'm asking this because I see so many build journals, they show the "how I built this studio", but not much of "why I did this the way I did"