The (also known as a Phase Oscilloscope or Vectorscope ) is an essential visualization tool in audio production that reveals the "hidden" relationship between the left and right channels of a stereo recording. The Story of the "Invisible Signal"
Understanding the Phasescope: A Guide to Audio Phase Analysis phasescope
Many playback systems (like club sound systems, phone speakers, or some radio broadcasts) are mono. If your mix relies on phase-shifted "stereo magic" to sound good, it might fall apart on these systems. The (also known as a Phase Oscilloscope or
– Tektronix (application note, but widely cited as a paper-level resource). Explains vectorscope graticules, 75% vs 100% color bars, and common phase errors. 75% vs 100% color bars