mr smith, you are correct. one cannot know which of 2 cables are less accurate0.
however, anecdotally, you might have confidence based upon listening, which of the two cables seems to alter the signal to a greater degree, at the listener position, using spectral analysis. i realize this is not a definitive test, and, as you indicate one cable may be preferred, but as a first step, it may provide some useful information.
however, anecdotally, you might have confidence based upon listening, which of the two cables seems to alter the signal to a greater degree, at the listener position, using spectral analysis. i realize this is not a definitive test, and, as you indicate one cable may be preferred, but as a first step, it may provide some useful information.