The Unipolar switch is represented by a small (+) button in the LFO section in the layer pages or with a “UNIPOLAR” switch in the SHOW MODULATION sidebar on the left. When it is not selected, the LFO will be in Bipolar mode. In Bi-polar mode the modulation corresponds to the mid-point of the LFO, meaning that the LFO’s output will stay above and below the mid-point. When the Unipolar switch is selected, the LFO is Unipolar, the LFO will above the mid-point and will double the range of its amplitude.
In the example below, the Oscillator’s pitch is being modulated with a Triangle wave from LFO1. If LFO1 is in BIPOLAR mode, the pitch will go above, then below, the pitch of the note that was triggered. In UNIPOLAR mode, the pitch would only rise above the pitch of the note being triggered—and the range of the pitch change would be greater.
For example, a Unipolar LFO applied to Oscillator pitch is great for simulating guitar-string finger vibrato, as guitarists can only bend strings UP with their fingers. Another use is for a Unipolar LFO to modulate the filter-cutoff. This will often create better filter sweeps than a bipolar LFO, as a bipolar LFO cycles below the mid-point, so no result is heard if the cutoff frequency is low.
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