This homework assignment combines table reading skills from week 2 (sampling in particular) with managing messages to line~ objects. The object is to play an electric (Hammond-style) organ sample (provided here), looping without a click using the overlapped cross-fade method, with on-off (amplitude) and pitch controls. There should be a third control to turn "portamento" on and off. Here's the "front panel" (visible controls) I brought out in my patch:

Your successful patch should be able to make sounds like this.

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

• Download the sample and have your patch read it into a 44103-sample table. (You can do this with loadbang and soundfiler objects). Make a patch driven by a phasor~ object to read the wavetable repeatedly. Using the cos~ object as shown in class, envelope the output so that it fades out at the endpoints instead of clicking. Putting a value of 1 into the phasor should play the sound back at original pitch.
• Make a second copy of the above, using a second phase that's 1/2 cycle from the original one (apply +~ 0.5 and wrap~ to the original phasor). Add the two to get a continuous output.
• Using mtof~, make a signal network that can convert the MIDI pitch 57 into a 1 Hz output (the original pitch of the "organ" sample has a pitch equivalent to 57 MIDI, equal to 220 Hz); you can use mtof~ and /~ 2 20. Then use pack and line~ objects to create an input to the mtof~ object that can slide between pitches such as 60 and 72 as shown in the screen shot.
• Make buttons to set the slide time for the line~ which is now controlling pitch. A good value for "portamento" (sliding) is 200 msec; a time of 0 means no portamento at all.
• Make buttons to turn the whole thing on and off by controlling amplitude of the output. This should also use pack and line~ objects, but the time value may be fixed at 50 msec.

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