Coax is preferred for long runs. Optical can and will break up over anything more than 20' or so unless the line remains straight and untouched. Once you start moving it around, it will break up. Both will have jitter, but the coax signal will be more stable. I have a 60' run of 75 ohm video cable that I use and it works jitter free 99% of the time. Occasionally, it will break up enough that my reciever will need to relock to the signal, but it's rare. Go with coax or video cable.
Here's a quote from the web:
Digital Audio:
Digital Audio is the usual mode for running multichannel audio from one device to another. The consumer standard, SPDIF, is nearly universal, and is incompatible with the professional standard, AES/EBU audio. In a digital audio cable, all of the audio for a number of channels is combined, digitally encoded, in a single bitstream. This may be conveyed from device to device either in an optical (Toslink) cable, or in a coaxial cable, so home theater cables for digital audio may take either of those forms.
Coaxial digital audio cable is, very simply, 75 ohm video cable. The same considerations apply; tight impedance tolerance and good shielding are desirable characteristics. SPDIF signals in coaxial digital audio cable can be run, without trouble, for hundreds of feet.
Optical digital audio cable is an odd beast. It is commonly assumed that the optical signal is more robust, because most people are familiar with the notion of fiber optic cable being used to run signals with huge bandwidth over vast distances; if a whole bundle of phone lines can be condensed into one hair-thickness optical fiber and run loss-free for miles, then certainly Toslink ought to be able to run for similar distances--right? Well, Toslink fiber is plastic, and, unfortunately, isn't at all the same thing as glass optical fiber, and there are technical problems with using glass fiber to do the job of Toslink fiber (notably, that the aperture of Toslink fiber is enormous compared with the size of glass fiber). Problems with Toslink can appear on runs as short as fifteen feet, though high-quality plastic fiber may extend that limit out considerably. When selecting a digital audio cable for home theater, if it's possible to run coaxial rather than optical, that's usually the best option, especially if significant distance must be covered.
There is also balanced digital audio--AES/EBU audio is conventionally run balanced, though it's not uncommon to see it converted to unbalanced form for long runs, and run in video coax, because of the tighter impedance tolerance of the video cable.
Topic: long length opti cables (Read 6638 times)