What Is A Spdif Cable ?
Also known as Sony/Philips Digital Interconnect format is a simple audio digital interconnect ( it carries all type of audio signals between a component and a device with the help of a electrical or optical cable – the optical solution is preferred for the quality of sound ) that is usually used for different types of audio systems over short distances most of the time. ( you will find definitions like SPDIF, S/P DIF, IEC 958 type 2 ).
The coaxial cables usually have some type of rca connectors and the fiber optic cables are equipped usually with toslink connectors.
The SPDIF can in most cases carry like a multi channel compressed surround sound or pcm audio formats similar to dts or let’s not forget, the dolby digital.
The type of signals that can be transmitted by the spdif cableare signals on cd/dvd players, pc audio cards, some types of car audio systems and any other system that is in theory and practice capable of transmitting and receiving digital audio signal.
Spdif cable
The principal manufacturers of the spdif cable are Philips and Sony and like a characteristic of this cable, you should know that two 192 bits blocks ( more plain, a right and left data channel ) is divided in 12 word and each of the word have 16 bits. For the control code, the first 6 bits are responsible.
What are the applications of SPDIF cable ?
By the standard named IEC 61937, the S/PDIF interface is used to carry compressed audio ( digital one ). You can also couple your own computer, getting digital sound with optical or coax to DTS/dolby compatible receivers.
More detailed characteristics of a SPDIF cable ?
Ok, ok, let’s advance further and talk about the connectors.
The equipment that you will have and that contains the SPDIF connectors is responsible for the determination of the data rate hand shake that comes from the mutual spdif signals. The audio hardware will accept these kind of signals.
Bi phase mark code <- sounds interesting ?
This code is used as the spdif protocol ( even deeper, it has 2 or more less, 1 transistors per bit ) and this will allow the extraction of the word clock from the base of the signal.
What are the most common SPDIF cable data rates ?
The answer is simple: the data rates can be of many types but the most used are the stereo cd quality audio ( 44.1 khz ) and the DAT also known as Digital Audio Tape ( 48 khz ).
The beauty of the spdif protocol is that it can actually support the 20 bit audio, comparing to typical spdif transmissions that are most likely to be limited to a 16 bitaudio.
This is not the end. The spdif protocol can also be adapted as we all know ( I hope so ) to support 24 bit audio.
Limitations of the spdif cable, or better said some negatives ?
Usually a receiver will not control the data rate and it will need to avoid the bit slip by synchronising with the source clock at the conversion level.
What implications this will have ? Well, as you probably guess, the spdif can’t decouple the last signal from the influence by the analogue characteristics coming from the source or interconnect even if the DAT-digital audio data is able to be transmitted without any loss.
Distortion or noise that can influence the data cable will also influence the process of the clock recovery. Also you need to know that if you use toslink cables in tight areas and you bend them, they will not work well.
Because it’s limitation in the flow control area and retransmission facilities, spdif has limited usefulness in almost any type of data communication application.
If I’ve forgotten something about spdif cables you can help us ( the community ) to better explain this by leaving a helpful tip in the comment sections bellow.