When it comes to digital audio, you have two options when it comes to choosing cables: optical digital audio cables, or digital coaxial cables. Either of these cables will let you set up your home audio or theater system in digital high quality that will transmit audio signals in digital, rather than analog form. The quality that they provide will invariably be much better than RCA audio cables.
What Are Digital Coaxial Cables and How Do They Work?
Like other coaxial cables (for example, the cable TV cable that is connected to your TV), these cables employ the same basic principle. They have an inner conducting layer that is usually made of copper. This layer is surrounded by an external conductor along with rubber insulation that wraps around the outside of the cable. The digital audio signal travels through the inner conductor, while the outer conductor (usually an aluminium foil) prevents interference and loss.
Unlike RF coaxial cables which transmit both audio as well as video, digital coaxial cable has just one purpose only: to transmit digital audio between two components. Obviously, this single function delivers much higher quality over RF coaxial cables, while minimizing signal loss and interference.
What Are the Benefits of Digital Coaxial Cables?
Besides the much higher quality that digital coaxial cable delivers, it has several other benefits too. In the typical scenario, a digital signal from a component such as a DVD player is first sent to a Digital-To-Analog converter (DAC) that, as the name suggests, converts the digital signal to analog. This analog signal travels through the medium (i.e., the cable) to the other component (say, a TV or speakers) which has an Analog-to-Digital converter (ADC) which turns this signal back to analog. Needless to say, this double conversion of the signal from digital to analog and back results in significant quality loss.
With a digital audio cable (i.e., both digital coaxial cable as well as optical digital audio cable), the audio signal can travel through a digital medium, thereby saving the use of the DAC and the ADC. Thus, the signal can bypass the receiver and deliver a clear, high quality digital signal.
You can find such cables on virtually every modern entertainment appliance, from home theater systems to DVD players to HDTVs.