A metal strip of tape indented with bumps that plays sound when inserted into the proper device, akin to a player piano tape. The device that plays the strip is called a resonance decoding cavity, and looks like a tall stovepipe-style top hat with no brim, mounted on a teapot stand, with a crank attachment and a trumpeted on its underside. To operate it, one feeds the tape into the cavity and turns the crank to run it through the device and create sound.

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