The restaurateur approaches the party of five in the booth, who are excitedly taking pictures of their food and posting it to Instagram.
The table laugh knowingly.
“No really guys. Just Be Sound. Literally. Turn yourself into oscillating waves of pressure composed of frequencies within the range of hearing.”
Another, quieter, burst of giggles.
“Be Sound. Just. Be. Sound.”
The people in the booth stop laughing and look at each other. Slowly, they all start to vibrate. A first it is a metronomic swinging motion, their bodies swaying back and forth. Eventually the oscillations become quicker and quicker until it looks like they are barely moving at all, aside from a faint glow around their edges. The cutlery on the table begins to move, propelled by the vibrations of the table. Gradually the rest of the patrons in the restaurant can hear a low drone, a gutteral sound, dark and sinister. This sound continues to grow as the bodies of the five people in the booth begin to fade into a vague miasmic cloud of form. Suddenly, as the sound reaches its climax, the five pulsing ghostly bodies explode outwards in a rippling sphere that moves out in all directions across the restaurant, smashing glasses and over turning tables and chairs. As the wave of sound hits people they immediately collapse to the ground and evacuate their bowels.
Suddenly there is silence, aside from the groans of restaurant goers writhing on the floor in their own excrement.
“Cool” the restaurateur says as he nods.