Magic Box => How It Works => Sound Wave
about "Sound Wave" : Sound starts as a vibration. Something has to move for sound to exist. For instance, you can ring a bell, clap your hands, or pluck guitar strings to produce vibrations that cause sound waves. Vibrations travel in sound waves from one place to another through the air. If the vibrations reach your ear, your ear will send a signal to your brain and you will hear the sound.