to know if you can substitute a digital coaxial cable to make a connection between sub and home receiver?
A: coaxial cable as in the home-cable kind? or the plug-n-play type?
either is fine if your connections allow for it, best way is to weigh the pro's vs. cons of either style of cable, and to ask if you really need to change, or are u getting the sound you want.
Coaxial:
PRO: wide range connections, easy to keep connected, clear signal, durable life.
CON: Hard to remove in tight spots, can receive interference if not shielded cable, cost a bit...