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Drawing in Automation > Drawing in Automation - Pg. 196

Phase Offset Modulation Along with generating a single waveform, the Subtractor oscillators can also generate a second identical waveform within the same oscillator. That second waveform's phase is then offset and modulated. Very complex new waveforms can be created with this process, which is called phase offset modulation. To begin offsetting the phase of an oscillator, you must first select one of three modes to activate this function. X--Waveform multiplication ­ --Waveform subtraction O--No phase offset modulation To better see how these waveforms look once phased, see Figure 9.3. In the first image, you will see a single Sawtooth waveform that contains no phase modulation at all. In the second image, you will see that same Sawtooth waveform, but this time it has been multiplied and a new waveform has been created. In the third image, you will see that same waveform again, but this time it has been subtracted and another new waveform has been created. To the left of the phase mode sectors is the Phase knob, which controls the amount of offset between the two waveforms within a single oscillator. Figure 9.3 Three graphical examples of phase offset modulation. LEARN BY EXAMPLE Phase offset modulation can be a difficult concept to grasp. As a personal preference, I generally find using a Subtractor patch that features this function is the best way to learn and better understand how it works. Browse through the various patches in the PolySynth folder and you will find several examples. A good patch to demonstrate phase offset is "The Plague" or possibly "Synced Up."