If you have a home theater system and want better sound, take a look at the back of your receiver. If there is a small square input marked either “digital in” or “optical in”, you are in luck. Here’s why.
Optical Audio cables are the equivalent of HDMI cables for video (see the Truth About HDMI Cables), except they only transmit the audio channels. The cables are made up of fiber optics and emit a red glow when the signal is active. You can also read a more technical explanation. You would use one if your receiver does not have an HDMI input/output. The sound is noticeably better than using RCA cables, which are the most common audio connections found in home theater. The format was actually developed by Toshiba and has been used in many high end audio products for years. It is now commonly found in any new HDTV, and most receivers will have them as well.
It’s important to remember here, that just like HDMI cables, there is no point in spending more than $3-5 dollars on one of these cables. You can get them on Amazon, Newegg, for about that price. If you wander into a large corporate electronics store, they will try to up sell you, no doubt about it.
Check to see how your television is hooked up to your receiver. If you are using RCA cables, and you have the option to use the optical line, you will immediately notice a serious upgrade in quality. Make sure you turn your receiver down, as the signal is much stronger and will be louder, as well cleaner when it gets to your speakers.