Recycled Sound

Everyone is familiar with the howl of a sound system which is turned up too loud. The sound comes out the speaker, goes back into the microphone and quickly builds up into a deafening howl. In RECYCLED SOUND, a long delay has been added, which slows down the buildup. This allows visitors to hear the transformation from speech to howl go through intermediate steps. Why does the sound change? If everything were perfect, it wouldn't change. But all along the way, the sound going through is influenced by the system. The microphone is not perfectly flat; it picks up some frequencies better than others. The speakers and the amplifier distort the sound slightly. But even with perfect components, the sound is influenced by the shapes and resonances of nearby objects. The plastic tubes or the seashell resonate at particular frequencies, and these are then picked up more strongly by the microphone. After enough trips through the system, the frequencies that are picked up the strongest dominate everything else. Only the strong survive, even in sound systems.