I have a hdtv cable box that outputs spdi/f coax digital out. I used a rca wire I had to hook it up to my reciever. The receiver displys that its getting a Dolby digital signal and audio sounds fine. I was wondering if a satandard RCA composite cable is the same as an spdi/f cable. My understaning of digital audio was that gold contacts dont matter since you cant really get noise with a digital signal. Am i correct? Is there a difference if a bought a cable that actually said spdif on the packaging. Thanks in advance.
No, as the whole reason for S/PDIF is that it uses 75 OHM cable (for coax cable) like everything else. Its just 75 OHM Coax cable terminated with RCA connectors. Its called Digital Coax because S/PDIF is a digital transmission. With that said, cables come in different builds. It is true that digital signals arn't bothered by the same types of interference analog signals are bothered by but buying a decent cable should still be a priority. To reduce the adverse effects "jitter" can have in a digital transmission (without error correction) you should look for adequate shielding (at least a braid and a foil) from outside interference not gold plating (Shielding also reduces the amount or radiation coming from the cable its self)! Although gold plating is found on many high end cables (not all!) it is not there because of its good conductivity gold is plated to the connector (connectors which are usually copper) so that the connections don't rust over time. Plating gold to the connector doesn't help in the area of signal transfer (Gold is actually behind Silver and Copper as far as conductivity goes). More often than not Gold plating is just something salesmen that don't know anything about electricity (or that think you don't) say will help your system preform better. They do so because they make more money on the gold plated crap cable over the silver plated crap cable. S/PDIF (Wikipeida) http://en.wikipedia.org/wiki/SPDIF Ced
