S/PDIF connection on the mainboard – optical audio output on the PC

Many PCs have an S/PDIF output on their mainboard, which you can use to transmit audio signals in stereo and multi-channel sound to other devices

S/PDIF connection – connecting devices

The abbreviation stands for the developers of the interface: Sony/Philips Digital Interface. The data is transmitted either electrically via a coaxial cable or optically via a Toslink cable.

• You can use the connection to connect your PC and an AV receiver, for example. The music signal is then amplified by the receiver and forwarded to passive speakers, through which you can then listen to the music from your PC.

• Of course, you can also bypass the receiver by using active speakers. “Active” in this context means that the speakers have an integrated amplifier unit. The connections are therefore located directly on the speaker and you can plug in your Toslink cable there, for example.

Advantages and disadvantages of S/PDIF

An S/PDIF connection has advantages, but also disadvantages. We will briefly discuss both aspects.

• Optical transmission is particularly advantageous in terms of interference. Electromagnetic radiation from other devices has no influence on data transmission.

• It is also practical that you can transmit multi-channel signals via one cable rather than several.

• However, the data rates of audio signals have increased rapidly in recent years. The bandwidth of the standard is not sufficient to transmit multi-channel audio in DTS-HD or Dolby-HD format without data loss.

• HDMI has strong advantages over S/PDIF here: 5.1 sound in HD format and picture can be transmitted via just one cable. This is why S/PDIF will probably be largely replaced in the home cinema sector.