layering the overtones of the fundamental pitch (A1, 55Hz) overtones work by adding the Hz of the fundamental pitch to the fundamental, ascending like 55, 110, 165 and so on for theoretically infinitely (9 in this case) every sound, save for VERY pure and artificial sounds like sin waves have overtones. overtones give noise a unique profile, which is how you can distinguish a piano playing A1 from a guitar.
