Digital Audio Cables

The cables and connectors used to interface various components in sound systems play a key role in enhancing your audio experience.

Digital Audio Cables

Today's audio devices no longer use analog signals to create sound. They use digital signals derived from data, namely, 0's and 1's.

The term ‘analog’ is used for phonographs and audio cassettes. Digital media includes CD's, MP3's and DVD’s, in which audio signals are processed by a chip to create superior sound. Digital audio cables are manufactured with the aim to preserve and transmit the digital signals, maintaining the highest possible quality. They come in two distinct flavors; coaxial digital cables and optical digital cables.

Coaxial Digital Cables

Coaxial digital cables are the most common type of connection cable used for digital audio. They look similar to the RCA cables that many people use and are familiar with. The only difference is that it carries digital signals instead of analog signals.

These cables look very similar to standard analog RCA cables. They are thicker than RCA cables and are shielded just like regular cable TV coaxial cables. The interference from outside signals is minimized with greater shielding.

Coaxial digital cables transmit digital signals in pulses of electricity. They consist of copper wires shielded from interference with the help of surrounding aluminum wraps. The wires are housed in a strong outer case. Coaxial digital cables used for audio applications have an impedance of 75 ohm, which means they can handle considerable energy. Also, they have a larger bandwidth than a normal RCA cable. For an affordable digital audio cable that delivers premium sound, coaxial digital cables are an extremely attractive choice.

Optical Digital Cables (also called S/PDIF, for Sony/Philips Digital Interface)

The other type of digital audio cable is the optical cable. Optical digital cables are the premier choice for transferring digital audio signals between components. They do not use RCA style connectors; instead they use what are called Toslink (or EIA-J).

These cables use pulses of light to transmit data, instead of copper wire. Since they are immune to interference from electromagnetic and radio-frequency interference, the signals do not degrade and weaken over long distances. Distortion caused by resistance, inductance and capacitance is eliminated, with the result that the best reproductions of digital signals are made possible.

Even though optical digital cables are more expensive, for true audiophiles looking for a superior experience with audio, nothing beats optical digital cable technology.

Since these cables get damaged when bent, they fail to work optimally if installed incorrectly.

Choosing Between Coaxial and Optical Cables

Many audio components allow both types of connectors, either coaxial or optical. Most users will not be able to tell the difference in sound. The circumstances outlined below show the pros and cons of both, and should help choose which cable is right for you.

1. Optical cables are a better option in environments with lots of electromagnetic interference, for instance, near personal computers or power cords sending out radio frequency noise.
2. Optical cables should be the preferred option for long distance transmission. While 3 or 6 feet won't make much difference, if you need speakers that are spread over 25 to 50 feet, optical digital cables are definitely the way to go.
3. In low budget circumstances, coaxial cables are usually more economical.
4. Coaxial cables are the only choice when the sound system set-up requires you to bend the cable to fit certain areas. Also, the performance of optical cables may get compromised if the system is moved frequently.

A Note about HDMI (High Definition Multimedia Interface) Ports

HDMI provides a way to carry digital audio signals.

However, it is mostly used in conjunction with video, for instance with DVD's, HDTV's and high definition DVD players. It is possible for HDMI ports to be included in ultra high end audio components, but the vast majority of audio components such as CD players do not include this option.