> An oscilloscope does not plot pitch vs time. You're right, it doesn't, and that's not what's happening here. It uses the X/Y deflection mode of the oscillosc

> An oscilloscope does not plot pitch vs time. You're right, it doesn't, and that's not what's happening here. It uses the X/Y deflection mode of the oscilloscope, plotting left channel vs right channel. If you don't believe it, play it on an oscilloscope yourself. (I have!)