I am using a standard RCA cable for digital coax out from my DVD to my reciever. I've had no problems with it and I've been using it for the last 6 months. My understanding is that the ''real'' digital coax cables are more expensive because they are manufactured to tighter tolerance standards while standard RCA cables are not. I also think the ''real'' coax cables are higher priced because people think that are completely different from standard RCA (which they aren't.)
Anyway, I suggest that you should at least try the standard RCA cable before throwing down cash on another cable. For analog signals the cable can make a big difference. For digital connections, as long as the signal gets through there is no difference in the quality from one cable to another.
Is there really a big difference between digital coaxial cables? I see a wide range of prices and don't want to cheap out and have the quality of the sound suffer, but also don't want to overpay for a name brand if there isn't a big difference.

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