To buy the expensive S/PDIF cables or not to buy the expensive S/PDIF cables? That is the question.
“I have a question about SPDIF cables. They are very expensive! I have used ordinary RCA cables to connect my digital equipment and they seem to work fine. Admittedly I make my own cables using the very best Belden wire & connectors. But am I losing anything this way? What’s the advantage of using bona fide SPDIF cables?”
The S/PDIF connections on equipment are designed to operate at a 75 ohm impedance. This is also true of the composite video connections that appear as a phono (RCA) type plug on a lot of video equipment. Sure, you can often get away with a standard audio cable, but it does degrade the quality of the transmission some. The degree of loss that occurs by using non 75 ohm cable (audio cable) will vary with many other factors, and in digital the difference is sometimes not noticeable. The absolute nature of digital tends to hide these subtleties. Your signal either arrives at its destination or not, right? At a basic level this is true, but there are issues like jitter that can degrade the performance and sound of digital audio. To reduce the chance of this type of trouble, we recommend using high quality 75 ohm cable for all S/PDIF connections. But it is nice to know you can just grab any RCA cable in a pinch.