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Analog-style sequencer

Example C08.analog.sequencer.pd (Figure 3.15) realizes the analog sequencer and envelope generation described in Section 3.7. The ``sequence" table, with nine elements, holds a sequence of frequencies. The phasor~ object at top cycles through the sequence table at 0.6 Hertz. Non-interpolating table lookup (tabread~ instead of tabread4~) is used to read the frequencies in discrete steps. (Such situations, in which we prefer non-interpolating table lookup, are rare.)

Figure 3.15: An analog-synthesizer-style sequencer.
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The wrap~ object converts the amplitude-9 sawtooth to a unit-amplitude one as described earlier in Figure 3.8, which is then used to obtain an envelope function from a second wavetable. This is used to control grain size in a looping sampler (from Section 2.6). Here the wavetable consists of six periods of a sinusoid. The grains are smoothed by multiplying by a raised cosine function (cos~ and + 1).

Example C09.sample.hold.pd (not pictured here) shows a sample-and-hold unit, another useful device for doing control tasks in the audio signal domain.


next up previous contents index
Next: MIDI-style synthesizer Up: Examples Previous: Signals to controls   Contents   Index
Miller Puckette 2006-12-30