mostly from watching how loud each test subject got in the traps? i knew that either way, the player would start yelling at or about something, so the aim of the decibel trap was to see just how quiet the person could be in order to survive. how the trap worked was i installed a decibel reader onto the trap and hooked it up so that every time her voice was above a whisper, it would start the machine up, inching the pipes closer to her neck - and in turn, her vocal cords. it was really really precise and required a LOT of medical knowledge for it to be executed correctly.