Spooky Sounds

Presentation

Teams entered the Snoqualmie Train Tunnel and heard a series of sound effects coming from a speaker array in the tunnel. On walking into the tunnel, they received the following recording sheet as well as a packet of these diagrams, and encounteed a dozen speakers set up in a rectangle around the space, all pointed inward and playing various sounds in cadence with each other. Each of the speakers plays a different track of sounds. A new sound clip plays every six seconds from each speaker (with a small clicking sound representing the case where there's no real sound playing from a given speaker at a given time). All of the tracks are synchronized so that the six second intervals hit at the same time, so that the sound data from speakers can be assigned to particular time slices. This puzzle cannot be solved online.