Have you ever wondered what the differences are between SPDIF and optical cables? These two types of connections have been around for a while. Toslink was first introduced as an alternative to coaxial digital audio connections. But what makes them different, and when should you use each cable type? Here’s our SPDIF vs. Optical comparison.
If you’re confused because your new speakers have both SPDIF and optical connections, fear not. In most cases, you can use either cable, but in certain situations, one might be better than the other to get the best audio quality. To begin with, let’s look at what each type of connection is used for and when they were created.
What is SPDIF?
Let’s start with SPDIF, which stands for Sony/Philips Digital Interconnect Format. It’s a digital audio connection introduced in the mid-1980s as an alternative to coaxial connections. The original goal of SPDIF was to reduce the interference caused by noise on regular analog audio cables.
It uses a computerized encoding system called PCM (Pulse Code Modulation), which encodes the data into binary form before reaching the receiving device. What? You thought this was a new technology? It’s been around for a while!
What is Optical?
Optical cable or Toslink came along later and is often used instead of SPDIF due to its greater bandwidth capabilities and better sound quality. Unlike SPDIF, optical does not use PCM but instead uses a different type of encoding system called TOSLINK (Transmission Output Signal Link). Toshiba first developed this technology in the early 1980s to connect digital audio players to their speakers.
Now that we know more about each type of connection let’s look at their main differences.
SPDIF vs. Optical: Main differences
The main difference between SPDIF and optical cables is signal transmission. As we mentioned earlier, SPDIF uses PCM encoding, while optical uses TOSLINK. This means that SPDIF has a limited bandwidth capability compared to optical, which can handle more data simultaneously.
SPDIF carries 2 channels (stereo), while optical can carry up to 8 channels (compressed surround sound) to enjoy your surround sound movies. SPDIF is also more susceptible to interference from other sources, using unshielded twisted pair cables. On the other hand, optical cables are much less prone to interference and offer better sound quality.
SPDIF uses electricity, while optical uses light to transfer data, making for a more reliable signal, free from interference. Another significant difference is compatibility – SPDIF is compatible with most home audio systems but is not as widely supported as optical. On the other hand, optical connections are more commonly found on commercial sound systems and professional DJ equipment.
SPDIF can only process digital signals and doesn’t support lossless audio formats like Dolby TrueHD and DTS-HD. Optical cables also can’t support lossless audio. That’s where HDMI comes in.
SPDIF vs. Optical: When to use each cable?
So, when should you use each type of cable? Optical cables are the better choice since TVs, Speakers, Game consoles, Smarthome devices, and more now support optical connections.
If your device has both SPDIF and optical connections, use the optical connection for better sound quality and reliability. Old media devices such as DVD and CD players may only support SPDIF connections, so you’d have to use a SPDIF cable.
Some audio interfaces require a SPDIF connection if you’re a music producer, while others may support both. There’s and advantage of using SPDIF since you don’t need to convert your audio signal from analog to digital. Because of this, you won’t have as much quality loss, and it can sometimes be convenient. Otherwise, go with the Optical cable for broader compatibility.
SPDIF vs. Optical cable: Pros and cons
To summarize, here are the pros and cons of each connection:
- Less signal conversion (analog to digital) required
- Widely supported by older audio systems
- Cheaper and easier to find than optical cables
- Limited bandwidth compared to optical cables
- Susceptible to interference from other sources
- It doesn’t support lossless audio formats like TrueHD or DTS-HD
- Can transmit up to 8 channels for surround sound playback
- Better sound quality due to less interference from other sources
- Compatible with most commercial sound systems and DJ equipment nowadays
- It still doesn’t support lossless audio
- The cable can be fragile and stop working as it works with light pulses to transfer data
- HDMI is replacing it with higher bandwidth and quality
Can you interchange them without issues?
Sometimes. Some differences between the two can cause issues if you try to interchange them. This mainly comes down to the type of encoding used and the varying data transfer speeds.
For example, SPDIF cables use a form of PCM (Pulse Code Modulation), which is incompatible with optical’s TOSLINK encoding system. You also won’t be able to output full 5.1 or 7.1 surround sound audio from a device using SPDIF over an Optical connection as it doesn’t carry enough bandwidth for this purpose. In short, it’s best to stick with their intended connecting devices if you want reliable results without compatibility issues or noise interference.
Is HDMI better than optical and SPDIF?
We mentioned in this article that HDMI supports lossless audio formats like Dolby TrueHD and DTS-HD. It can provide better sound quality than SPDIF or Optical cables. HDMI can have higher bandwidth (depending on which version) and pass higher-resolution audio than SPDIF or Optical cables. It also supports video, so you can connect your device to a TV, for example, and get audio and video without using two separate cables.
HDMI cables can be connected to sound bars and receivers, so you can listen to lossless audio from your TV while transferring 4K or 8K video without issues. In most cases, HDMI can be the best connection for both audio and video.
SPDIF vs. Optical: Wrapping things up
Now you know the differences between SPDIF and Optical cables. Both are widely used for audio connection. Optical is the better choice in most cases as it supports surround sound and can be connected to more devices unless you need SPDIF for some very specific (or old) devices.
Also, remember that HDMI is better than both nowadays and can transfer video. While the cable might not be as thin and flexible as Optical cables, it’s a better choice for most situations as you run everything through 1 cable. And most people have HDMI cables around the house. At the end of the day, make sure you get a good quality cable that fits your needs and budget. We hope this article helped you decide which cable is best for your setup!