This assignment is intended to give you practice with timing, counting, and controlling line~ objects. In essence it is make a pair of tones that fade in and out alternately, to play a series of four notes, overlapping. The timing should be as shown here:

The pitches are in the sequence (60, 65, 62, 70), repeating. (You can replace these with your own if you want.) One complication: in order to get practice using parameter values, your patch should have a control (a number box) to set the amount of time each sound takes to fade in (called the "rise time").

Your successful patch should sound like this.

To make the patch:

• Make a waveform-based oscillator. This is the same mechanism that you used in homework 2, except that you'll only need one copy (before you needed two overlapping out-of-phase ones). The waveform need not have more than, say, 500 samples in it. The one used to make the example sound was 103 samples long.
• Set up three "receive" objects: one to set the pitch, one to turn the amplitude-controlling line~ object off over 1000 milliseconds, and one to turn the line~ on (up to a value of 1) with a "rise time" being a variable number of milliseconds (That is, the message it receives should be a number containing the desired rise time.)
• Make a control (a number box) that sends a numeric value for the "rise time". This should be a separate "send" object. Its value should then be stored, where needed, by "float" ("f") objects, which then become the messages sent to the line~ that starts the sound (and thus needs that value).
• Once this is working (say, for the "60" and "62" sounds, so that you can make them alternate without clicking or suddenly changing pitch while they're already playing), make a second copy of the sound-making portion of the patch, including the three receive objects, but change the names of the receives so they can get their own messages. Add the outputs of these two copies, and then add a master output control (controlled by another line~ and number box as usual) and output them.
• Make a counter that counts repeatedly to 4 (as in 0, 1, 2, 3, 0, 1, 2, 3, ...), one second per count. At each of the counts, send messages to the various receive objects to start and stop sounds in the repeating sequence shown in the picture.

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