the difference is between analogue and coaxial, the jb's dac is better than the marantz i believe,
and when used this way it shows, bye the way a cd63se is a good choice aswell.
ive also used a denon dcd 825, the results were a little closer with that one as they use burr brown dac's,
they are decent price just now, they have variable output adjusted with the remote, if thats missing you
would need to use a programmable one as the default volume is not the loudest position.
these are old but good girls and now are getting age related issues eg laser, which are cheap and plentiful,
denon used a sony and marantz uses a phillips type, the 5v regulator can go bad an the marantz, easy fix,
symptom of that is no switch on.
they dont make them like they used to, these are better built than todays rubbish.