Editing : Editing Basics : Audio Clips and Waveforms : Rectified Waveforms

Rectified Waveforms
Rectified waveforms are displayed so that their positive and negative waveform excursions (the portions that fall above and below the center line) are summed together and viewed as a single positive-value signal. This view lets you see more waveform detail in normal or reduced track height views. It can be particularly useful when editing volume automation data, since it depicts waveform levels as starting at the bottom of the track. Rectified view is available in both Peak and Power views.
To show waveforms rectified (or normally):
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Select (or deselect) View > Waveforms > Rectified.
 
 
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When zoomed in to the sample level, Pro Tools always displays waveforms in Normal Peak view.