Music 171 homework 5

This assignment is designed to give you practice with making abstractions and also to introduce non-linear distortion as a synthesis technique, using index of modulation and evenness/oddness to control timbre.

The assignment is to make a patch that plays a five-note chord (in my example, I just fixed the chord as having pitches 60, 62, 65, 67, and 70. A chord is a sound containing more than one note played together at once.)

The synthesis algorithm should consist of a sinusoidal oscillator, with an amplitude (an "index of modulation") and an added onset between 0 and 0.25, sent to a cosine function to distort it. The technique itself is described in class and also demonstrated in the Pd example E07.evenodd.pd.

Your successful patch should be able to make sounds like this. One individual note of the five (the one playing MIDI pitch 60) sounds like this.

To make the patch:

Although you could just use the out1~ gain control to set the amplitude it is a good idea to include separate amplitude controls in your patches because, when you want to combine several different kinds of sounds, you will want to be able to control them separately and still have a "master" level set by an out1~ object.

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