so this device, called an oscilloscope, beautiful, allows us to see the shape of waves. very, very nice. wow. where it's extra loud, a compression from one fork and a compression from the other have reached your ear. and where it's very low, a compression is matched by a rarefaction, in one fills and the other, it makes it like null. isn't that nice? beats. question, paul? can you explain why laser discs are suppose to have a better sound quality than tapes? those laser discs amaze me. let me tell you what a laser disc does. you saw ted sang in here and showed you a particular wave. well, when ted did that-- ted maybe made a wave like that. now, what i wanna do is i wanna record that wave and give it back to you. the old way of doing it was just to have ted speak into a microphone, and when he spoke into the microphone, a little crystal would start to vibrate too. and the crystal vibrates like that, the electrons get squeezed up here and spread out here so that just pass through the wire. and as the crystal vibrates, the little electrons will vibrate too, just in rhythm,