Why are optical cables jitter prone?

In my system I am forced to use Toslink. I am currently using the Chord Optichord from the UK. IMHO it is much smoother and clearer than the Monster or Kimber optical cables. A new optical cable from Van den Hul has also received some good reviews and is reasonably priced.

Is it easier to build optical--fiber optic--outputs? I've seen some of the cheaper DVD players that only have coax outputs, i.e. my Toshiba DVD player for my second TV, while on the other had players like the Sony Playstation seem to only have optical outs. It might be a manufacturing issue that we are missing here. I personally use the Kimber Illuminations D-60 coax for my main system. I will never go back to optical, but I was just curious if it is a transmission technique that will get better in the future. I always assumed that the optical cable we could buy non-commercially was not up to par quality-wise with the fiber optic stuff that Sprint and others are putting in the ground. But perhaps distortion is not as big an issue with them--however I would have assumed it was considering the amount of traffic on the lines.

Light is a very good medium for transmission. How the light is created is the problem. Inexpensive toslink based light sources spray the light at the end of the cable at a very wide angle. Inside the cable, the light travels mutiple paths (multi mode) - some light travels directly down the length of the fiber to the destination, other light takes a bouncing path along the length of the cable, arriving later than direct path light. This bouncing (and late arriving) light is carring the same information as the direct light. Hence jitter. Single mode transmission via fiber optics uses a very narrowly focused beam of light at the end of the cable. The light travels a direct path through the fiber without internal reflections - SINGLE MODE - Many of you have seen this option available on higher end transports and processors. It's not the light that is the problem, it's the way it's put on the fiber. The best explination of this is available from the computer networking industry, (network essentials study guides) where fiber optics are used on regular basis.

3728 is quite right. "Optical" cables have taken a bad rap recently largely due to the confusion between toslink (plastic connectors with multi-mode fiber) and "AT&T" (ST-type connectors with single-mode fiber). There are also differences due to the transport/DAC manufacturers knowledge and concern in execution of the optical driver/receivers. In other words, not all optical interfaces are created equal. Goldmund digital is a perfect example. The optical interface was not just an afterthought, but a preferred engineering solution even though it is offered as an "optional" input/output on their products. As always, use your ears to determine what works best for you in your system.

I have read many places that Toslink cable actually rejects jitter better than Coaxial cable, but the big advantage of coaxial is its much greater potential bandwidth transmission and more robust conectors. Audio mags., such as Stereophile, do not recommend Toslink because of it's low bandwith transmission compared to coax. Craig.