I've done combat training in one (a 3-story aluminum sided building furnished like a large office) and they had rigged the whole building with an interactive surround sound system. Once the course started and we got up to the building, I thought I heard music coming from inside. We opened the door and Metallica was blasting at 120db and none of us could hear each other. We had to communicate using signals while navigating the course with fake hostages and combatants etc. all while Master of Puppets was assaulting my ears. You couldn't escape it either, we were being sound-gunned on every floor and every room.

Anyway, just thought I'd share since Sound is something people forget when imagining training in these buildings and the experience was invaluable.