Music 171 homework 2
This assignment is to make a Pd patch to produce a tone that starts as a pure sinusoid but, under control of a toggle switch, fades in three harmonics to make a "complex" (non-sinusoidal) tone. The transition should be smooth so that you hear the first timbre evolve into the second one. When the toggle is switched off again, the sound should smoothly "morph" back into the original sinusoid. Here's an example of how this might sound. In this example, the fundamental frequency is 220, and there are only four partials (fundamental and three overtones. The partials' amplitudes are less than the fundamental; if you gave them all the same amplitude the sound would be pretty harsh.)

For extra credit, apply vibrato to the even-numbered partials (under control of a second toggle switch) so that, after you turned the first toggle on to make the sound "complex" (be non-sinusoidal, i.e., have overtones), the second toggle makes the even-numbered overtones in the patch change their pitches in sync, oscillating around their nominal frequencies. This should make the sound appear to split in two, as in this example.

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