1960s style sequencing revisited

This assignment combines practice with modulation (chapter 5 of the book) with another sequencer-like trope that came into being in the days of voltage-controlled synthesizers: randomness (in the 60s done using a noise generator and a sample/hold unit but today more easily managed in the control domain with a metronome and random number generator; here we'll opt for the second possibility). The working patch should make a series of random notes and "play" them using a waveshaping instrument (to use the term loosely) that uses symmetry to vary from even to odd harmonics.

To make the patch (as usual, 2 points for each step below):

• Make random numbers ranging from 36 to 72, controlled by a metro object to generate six to eight notes per second. The 'random' object will help you.
• Make a waveshaping patch as in patch example E07.evenodd.pd (the last example described in chapter 5 of the book). The heart of the the patch is the oscillator and cosine generator, with an envelope generator to control the gain of the oscillator into the cos~ object, and an adder to make an offset to control evenness/oddness.
• Rather than use an abstraction for the envelope generator, make it simple and just supply a line~ with message boxes in the patch. (Note that it's possible to be lazy and not make a second envelope generator to control the amplitude of the output; if the "index" goes to zero the output is a constant and hence silent.)
• To make the patch vary continuously from evenness to oddness, make a second oscillator running at , say, 0.1 Hz., that generates an offset for the cos~ object (in the example, this is just supplied by message boxes). You will have to use a multiplier and adder to adjust the oscillator's natural range (from -1 to 1) to the range 0 to 0.25, so that it functions as an even/odd harmonic control.
• Since this patch can make constant, non-zero output, use a hip~ object (high-pass filter) to remove DC from the output; a 5-Hz. cutoff is fine. Then make some reasonable way to control the output amplitude overall.

Your successful patch should sound something like this.

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