Tunable organ pipe.

Vibrating Air Columns: A tuneable Organ Pipe. A piston may be inserted in an organ pipe to alter the size of the resonant cavity. Or, the lid may be closed toshow the change in the resonant frequency. This tunable pipe may be included on the compressed-air organ base along with the other organ pipes, or it can be operated individually. (See B+50+20).
UCB Index: 
PIRA Index: 
Demo Diagram: