An optical audio cable, commonly known as a TOSLINK cable due to its origins as the TOSHIBA cable, is a fiber optic connection that is fast becoming the standard for audio cables. Optical cables are based on fiber optics that converts audio and transmits it through light, usually red LED light. Before buying one, there are a few things to know.
Any length that exceeds 10 meters is a poor choice, as it reduces the reliability of the transmission. Most optical audio cables will be no longer than 5 meters without a signal booster. If you need lengths greater than one hundred feet, an optical cable made from melted quartz is the best option, as it will produce better quality. If all you need is a short cable, you can use a cable with plastic optical fibers, as no difference in quality will be detected unless you are over a hundred feet away and transmitting at high levels of bandwidth.
There is no difference in performance between 5mm and 8mm as it is just the outer diameter of the cable and therefore does not affect the connectors at all. However, you may want to consider that thicker cables are more durable and generally come with a protective nylon mesh cover on the outside.
Optical audio cables don’t differ much from brand to brand. Unless you have a good ear and have a remarkably loud system, you are not likely to hear any difference when using a cheaper brand than when using a more expensive brand.
Compared to digital coaxial cables, optical audio cables can be a bit more expensive. But in return, they offer better performance when it comes to reproducing digital signals, as there is no interference from surrounding electronic devices. What will greatly affect your price is the type of optical cable you invest in. The standard 5 meter plastic fiber cables are drastically cheaper than the quartz cables mentioned above. Some cables may come with 24k gold-plated connectors to improve signal transfer and help prevent corrosion, and this can also greatly increase the price.
It’s a good idea to make sure there are no sharp kinks in the optical audio cable, as this will cause it to malfunction or not work at all. Bends are correct and unavoidable, but bending prevents the LED light from transferring properly along the cable.
For the best performance, your cable should have a bandwidth of 9MHz to 11MHz. The higher this bandwidth, the better it will work. Keep in mind that smaller consumer products such as CD players will not see a decrease in quality due to low bandwidth in the way that a home theater system would.