UPDATE; with phasiing turned on as in step 5 below, the patch should rather sound something like this.

To make the patch (each of the following steps is worth 2 points for a total of 10):

• Download this flute recording. Load it into an array in your patch. (You can use the soundfiler object to load it; be sure to use the "-resize" flag to get the array resized to the size of the soundfile. Make the array save its contents using the properties dialog, so that you don't have to make the patch automatically load it each time. (This flag can reset itself spontaneously so make sure it's activated.)
• Using phasor~ and the technique shown in class Thursday (adding 0.5 and using the wrap~ object), make two phasors that are one half cycle out of phase, to read into the downloaded array. Use the windowing technique (also shown in class) to control the amplitude of each one of the two tabread4~ outputs so that they are zero at each moment the phase wraps around from 1 to 0, to avoid hearing a 'click' sound.
• Make another array, with 12 elements. Its y-value range should be set from 2 (for example) to 0 as you descend from its top to bottom. This table should control the frequency of the phasor~ object described above, so that you hear a sequence of 12 different speeds of playback (which will sound like 12 different musical pitches.) You will have to use another phasor~ object to read the values in sequence, and a tabread~ object (no interpolation!) to read the 12 values. This is the same operation as reading the flute array except that the table only has 12 values instead of the many thousands that the flute array will have. When you have this working you should hear a sequence of 12 audible transpositions of the flute sound.
• Find reasonable frequency for the controlling phasor~ object, and reasonable values to put in the 12-element array (which controls the pitches), and a reasonable range of values over which to read the array holding the recorded flute sound. Once this is working you should hear a sequence of 12 pitches that repeats forever.
• Once you hear the sequence of pitches, you can then duplicate the entire patch, this time using a slightly different frequency (only 0.1 or even 0.01 different) to get the effect in the example. Make sure that the patch you make makes sound as soon as you open it and start DSP.

Note: the included flute recording was downloaded from freesound.org. It's on a Creative Commons license (attribution; non-commercial), uploaded by Carlos_Vaquero.

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