"Numerous very small holes are drilled at lengths through the top of the tube and propane or a similar gas is fed through it. By forcing sound waves into the tube through a speaker at one end, varying areas of pressure are created. The higher flames occur at points of higher pressure (nodes) and smaller flames at lower pressure (antinodes)"
On the video a guy demonstates how to manipulate sound with his wiimote to cause the flames to change height, shape amd pattern. Check it out... Fire and a wiimote!
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