Achieved by transferring vibration to running water.
Tape a vinyl hose to a speaker, run water through it, produce a 24 Hz sine wave, and turn up the volume. Your brain’s frequency is much higher than that of a camera, so you must use a 24 FPS camera in order to see this effect. Technically it’s a water trick. The water looks like it freezes. If you increase the frequency you get a slow motion forward effect. Decrease the frequency for a slow motion reverse effect. I used an amplified 12″ infinity kappa at 700 watts.
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