The Uni-polar switch is represented by a small (+) button. 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 Uni-polar switch is selected, the LFO is Uni-polar, 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 Sine wave from LFO1. If LFO1 is in bi-polar mode, the pitch will go above, then below, the pitch of the note that was triggered. In Uni-polar mode, the pitch would only rise above the pitch of the note being triggered and the range of the change in pitch would be greater.
For example, a Uni-polar LFO applied to Oscillator pitch is great for simulating guitar-string bending, as guitarists typically bend strings only in one direction. 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 bi-polar LFO cycles below the mid-point, so no result is heard if the cutoff frequency is low.
NOTE: If you want the value needs to go negative instead of positive, simply select the INVERT button in the MODULATION section.
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