<p>^^We visited CMU my son’s sophomore year too, and he liked Pittsburgh and the overall feel of the school but did not like the vibe in the theater department. It wasn’t an “official” visit with tour, etc.–we just wandered around, got a sense of the people and atmosphere, etc. I don’t remember the smell…but in a similar vein, when my daughter visited colleges, she had this compulsion during every tour to hang behind the group when we visited a theater and go down and <em>touch</em> the stage–she wanted to see what it was made of, as I recall! She eventually majored in theater with a focus on set design, so I guess the hands-on thing was a sign of things to come. 
Maybe that “smell of the theater” thing is similar for your son!</p>