A busy hallway ambiance of a university or business setting.
Several children playing or speaking at a school assembly.
Large rolling metal prison door rolls to a close in a empty prison setting.
A stewardess announcing the completion of boarding over a airplane intercom.
A city office room tone with air conditioner sounds and a distant vacuum.
A crowd bowling alley during a game.
A quiet office room tone with metal file cabinet sounds.
Heavy rainfall onto a tarp or plastic surface.
A crowded pub or restaurant with crowd chatter.
A large boom of a prison cell door shutting.