Assignment 5 is to make a major triad (three-note chord) morph into a single tone whose pitch is the common subharmonic of the three. If the pitches in the chord are 60, 64, and 67 (roughly the ratio 4:5:6) the resulting tone will be 36 (1/4 the frequency of the lowest tone in the triad).
I made the tones using a simple waveshaping instrument, but could have used an oscillator with a complex waveform, or FM, or whatnot. For the example to sound good the result should have most, but not all, of its energy in the fundamental.
The sum of the three goes into a "clip~ -1 1" object, with a controlled amplitude. As long as the peak amplitude is less than one going into the clip~, you get the three tones separately. But when the amplitude increases the three start to intermodulate and you hear the lower, resultant tone.
To make the effect, start the amplitude out at a lower level, increase it until the resultant tone comes out, then decrease it to the original value so that the tone splits back into the original three.
Here is my sample output.