Do you want to get the highest possible sound quality from your audio installation and do the components have an S / PDIF tulip connection? Then use a digital coaxial cable to connect the components together. A digital transmission does not suffer from signal degradation compared to an analog connection, provided you use a digital coaxial cable of sufficient quality.
Does one component have an optical toslink and the other a digital coaxial connection? Then order an optical converter with which the components can still be connected to each other. With an inverter you can also connect analog equipment to a digital coaxial cable input or output.
List of Best Digital Coaxial Cables:
What is a Digitized Audio Signal?
Much video and audio is offered digitally via for example DVD, Blu-ray disc or via streaming services over the internet. A digital signal has some important advantages over an analog signal. It is much less sensitive to external influences and has little signal attenuation in cabling. If the signal level remains above a certain threshold, the digital video or audio signal is flawlessly decoded by the receiving device.
HDMI is the best-known connection standard for transferring digital video signals with accompanying audio. S / PDIF [Philips Sony Digital Interface] is the most widely used connection standard in the consumer audio world for transferring digital audio signals. This can be used to send an uncompressed stereo audio signal or to send compressed 5.1 / 7.1 surround sound. This makes S / PDIF suitable for transferring a high-quality digital stereo signal from CD and DVD, but also suitable for transferring the surround sound signal from a film to a home cinema set. This has ensured that it has become a widely accepted and widely used digital audio connection.
Two types of Digital Audio Connections
S / PDIF supports two types of connections: the electrical connection and the optical connection.
An advantage of the electrical connection is that it keeps the costs of equipment low. The digital signal is already available in a device and only needs to be buffered before it is sent outside.
The electrical S / PDIF connection uses the tulip connection that is widely used in the audio world. When using the electrical connection, it is important to note that a standard audio tulip cable is not sufficient for signal transmission. With a normal audio signal, the frequency range of the signal ranges from about 20 Hz [Hertz] to about 20 KHz [kilohertz]. Such a signal can be sent via a well-shielded cable without any audible degradation of the signal. The digital S / PDIF audio signal has a bitrate of a few megabits per second [Mb / s]. A much wider bandwidth than an analog audio signal is required to transport this signal.
What is a Digital Coaxial Cable?
Because a digitized audio signal has a bit rate of a few Mb / s, cabling with sufficient bandwidth is required so that the digital signal arrives at the receiver without much distortion.
In theory, the cabling bandwidth in Hz should be at least twice the bit rate per second. In practice, this is done at least three times, but the higher the bandwidth of the cabling, the easier the digital signal can be recognized by the receiver.
A standard audio cable has insufficient bandwidth, which is why a coaxial cable is used for S / PDIF. Standard commercial coax cable has a bandwidth of a few hundred megahertz and is therefore an excellent transport medium for an electrical signal. Digital signals with a frequency of a number of megahertz behave like high-frequency signals, creating a fixed relationship between voltage and current. The ratio is called impedance and depends on the construction of the cabling.
A coaxial cable with an impedance of 75 ohms is used to transport an electrical S / PDIF signal. The RCA plug, which is well-known in the audio world, has been chosen as the connection.
How to Select a Correct Digital Coaxial Cable?
When ordering a digital coaxial cable, it is important to know that you are ordering a genuine coaxial cable and not a shielded analog audio cable. A digital coaxial cable can be recognized by the cable thickness. This is about twice as thick as a standard tulip audio cable.
Since the digital audio signal contains both stereo channels or with surround sound all surround channels, you only need one digital coaxial cable to connect a digital audio signal. This is in contrast to the standard stereo signal where both channels have their own connection.
To ensure that the digital signal is neatly enclosed in the wiring so that it does not cause interference in other cables or equipment, a digital coaxial cable often chooses to use a double-shielded cable. The first shield often consists of aluminum foil and the second shield consists of a braided copper screen. For the quality of the signal transmission, it is important that you do not cut, shorten or extend the cable yourself. Therefore, first measure the length you need and then order a cable of a suitable length.