This assignment is to make a movie-soundtrack-style foghorn sound. IT is designed to exercise your ability to connect phasors and table lookups, both interpolating and non-interpolating.

Your successful patch should sound like this.

To make the patch::

• Using a phasor~ and a table lookup (non-interpolating), make a signal that takes the values 100 and 60 (for example), going between the two with an overall period of 5 seconds. (The table only needs two values in it. The phasor~ output should be adjusted to have a range from 0 to 2.)
• Using that as the frequency for a second phasor~ object, and adjust that phasor's range to 1 to 301 (for example), and use that as an index to a second table that holds an audio waveform. You can draw the waveform by hand and/or record something into it.
• Make a second frequency signal about 1/3 Hz. higher (just add the value to the output of the frequency table), and use it as the frequency for a second audio waveform lookup similar to the previous one.
• Add the two detuned audio waveforms and apply an amplitude control to the sum to allow turning the sound on and off. When 'ON' the amplitude should be reasonable (say in the range 0.1 to 0.3).
• Make message boxes to turn the patch on and off and set the tables to save their values in the patch (so that you don't lose the values when you close and re-open the patch). Test it to see that when you re-start Pd and reload the patch, all you have to do to hear the sound is to click a clearly marked message box that turns the output amplitude on.

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