supposedly, although a regular old rca cable will carry a digital signal, it has a different impedance and/or looser tolerances than a specially-designed digital coax cable and thus will experience more signal degradation. on the other hand, digital coax and video composite cables are both designed to have the same characteristic impedance (i think 75ohm) and should perform the same. i'm sure the cable acolytes out there can point out some major differences, but i can't hear any.
to which end, i use garden-variety belden or acoustic research digital coax cables, which you can get for ten bucks or less at parts express or amazon.
to which end, i use garden-variety belden or acoustic research digital coax cables, which you can get for ten bucks or less at parts express or amazon.