[Justb]

Old Thread, but thought I’d weigh-in for the next bloke who’s searching for this.
One can easily identify waveforms that are in or out of phase by placing them side/by/side, zooming-in to see hills and valleys of the waveform, and check if the hills and valleys are opposite or in sync with each other between the two tracks you’re comparing. Of course the tracks need to be in time-sync by placing both at the same starting point so the time delay doesn’t give a false impression of phase. That, or you could just use an EQ with a phase adjustment option and test in MONO with or without the phase inverted. Hope that helps!