phase problems basically occur when the waves in the left and right signals in a stereo
signal principally get out of sync (way over simplified but its an effective
in a worst case scenario they can cancel each other out
entirely (an effective studio tool) but in more practical terms cause an imbalance in the
perceived energy of the song.
the brain can be very good at spotting this with the
effect that a song can sound lopsided even with both left and right channels at exactly
the same volume.
over use of stereo width creation plugins or effects can
create the problems highlighted above by shifting sounds with a wide image already into
similarly delays can also cause the same effect of phase problems and
another very common source is recordings made with a stereo mic.
world of digital media and CDs, phase problems in a final track, especially momentary
occurences can easily be left so long as they do not create a feeling of incorrect balance
or an obviously audible negative impact on the music however if pressing onto vinyl they
can cause the needle to jump out of the groove and thus render a recording useless if
a check is used in nearly all mastering applications to point
out potential problems within a source material, i use it without fail, however appearance
of such artifacts does not always mean that theres something terminal within a mix or the
high quality audio mastering for vinyl and cd.
point one mastering