Set the frequency you want to reduce using the Frequency knob. You can click the Filter Solo button to make the frequency easier to hear and identify.
Drag the Threshold knob to the level at which DeEsser 2 should start to apply reduction. To set a narrow frequency range, click the Split Range button. To set a broader range, click the Wide Range button.
Drag the Max Reduction knob to set how much sibilance to reduce. The Reduction meter shows how much sibilance DeEsser 2 is attenuating.
Note: Be prudent with how much reduction you apply. Sibilance is a natural part of speech and removing too much may make your vocals sound strange.
Download the guides:
Logic Pro User Guide: PDF