What is phase rotation?

Changing the phase by 180 degrees is the same as flipping the polarity. Polarity is either flipped or not. Phase can be anywhere in between.1

Phase rotation is helpful for getting two different sources in phase as well as making asymmetrical waveforms (see Asymmetric saturation curves) more symmetrical, which can reduce Crest factor.2 Phase rotation can also increase crest factor, as discussed in Have no fear about high-pass filtering.3

Phase rotation changes the frequency amplitudes, but not the frequency content.4

  1. Fixing Phase… What, Why, When and How ↩

  2. Mixing Tutorial: Phase Rotation - YouTube ↩

  3. Delay Always Means Phase Shift But Phase Shift Does Not Always Mean Delay - YouTube ↩

  4. “Phase Shift” vs “Phase Rotation” - Gearspace.com ↩

Notes mentioning this note

All about phase and polarity
All about phase and polarity Phase is a function of time. Polarity is a function of positive and negative. Shifting...