Why are optical cables jitter prone?

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.

My toslink connection between a Pioneer DVD player and Bel Canto DAC1 works very well. There is some info on the Bel Canto site on their theories as to jitter reduction. Stan Warren also agrees that it is jitter reducing in this type application. He did recommend a particular toslink cable as sounding much better to him and his buddies. It was the Audio One Reference, I believe. I use an ER-Tos by XLO, 2 meter, right now but will give his recommendation a try. Charlie

I have not used toslink but have heard -- from those who have used it and are credible -- that it is important to use glass rather than other materials. FWIW.