Why are optical cables jitter prone?


A friend of mine convinced me to purchase an electrical (RCA jack) digital cable for the home theater. He said that even though optical looks neat, it is extremely succeptible to jitter. I thought both kinds were. But, low and behold, I switched to the RCA type and my bass immediately got louder and tighter. Does anyone have a short and sweet explanation as to why? Thanks.
argent
Hi everyone, Bjack, Danvetc, Just thought to pass along some info. I needed a Toslink cable for my Denon MD-1000 minidisc recorder, as it does not have coax out. Last week I compared 4 cables. The El Cheapo that came with the unit, Monster's$40 model, the van del Hul, and the Audio One Reference. The van del Hul was slightly better than the Monster and the El Cheapo, and the Audio One Reference was the clear winner of the face-off. It had a more balanced presentation. The bass seemed to rejoin the music, vocals were smoother and less tinny and the cohesive sound enabled me to enjoy the music without being too distracted by the edgy quality of the Minidisc format.
Hope this helps, just in case thinking turns to buying.
Forgot to mention that Robert Stein from The Cable Company told me Audio One does not use any special wire or components, but they assemble their optical cables to "very high tolerances", and evidently it makes a difference in sound quality. I guess that means very accurate and careful assembly. Maybe that has something to do with reducing jitter. I am not as informed as some of the more technically inclined here, and perhaps someone can shed a bit of light on the subject (pun intended).
Normally in a manufacturing sense it is harder and more expensive to make something with a tight tolerance. Not sure if he just stated himself wrong, but having a "high tolerance" means having a loose fit. I would expect optical cable dimensions to be critical, and thus need to be as exact as possible. Can anyone else fill in the blanks here?