A digital optical audio output (also called TOSLINK) and an HDMI port are present in almost all televisions and soundbars. Both transmit TV audio signals to soundbars or audio video receivers and are readily available at different rates.
HDMI ARC (Audio Return Channel) allows you to transfer audio and video signals together, while optical audio cables are limited to audio only. So if your TV and soundbar have both ports, what do you do? Which should you use?
Well, that’s what we’re going to discuss in this article today and dive into the basics of digital optical audio cable and HDMI ARC to determine which audio cable is best for your needs.
Without further ado, let’s get started. But first,
What is HDMI ARC
HDMI (short for High-Definition Multimedia Interface) is the interface for carrying video and audio signals between the TV and game consoles, streaming boxes and soundbars. Traditionally, HDMI cables are copper. However, you will also find fiber optic HDMI cables and they are quite expensive.
The use of copper in HDMI cables makes them affordable. However, this also makes it prone to electromagnetic interference generated by powerful electrical devices. Fortunately, such interference is not common in normal home setups.
That said, HDMI has seen quite a few iterations since its inception. Now, HDMI 2.1 is the latest version that you would likely see in the latest and most popular electronic devices like OLED TVs, game consoles like the PlayStation 5 and Xbox Series X, soundbars, and audio video receivers.
Traditionally, HDMI could only transfer video. And in 2009 it welcomed the HDMI ARC protocol to facilitate two-way communication for audio and video. So, if you have a compatible TV and soundbar, you can use a compatible HDMI cable to transmit audio from your TV to the soundbar.
However, HDMI ARC is not without limitations. For one thing, it can’t transfer high resolution audio. The maximum audio bandwidth of 1 Mbps means it cannot support modern lossless audio formats such as Dolby Atmos, DTS-X or Dolby True HD.
At the same time, it does not support 7.1 channels. However, it should be noted that HDMI ARC supports Dolby Digital Plus. For those who don’t know, Dolby Digital Plus has twice the efficiency of Dolby Digital audio technology and is usually found in online streaming services like Netflix, Amazon, Hulu, etc.
What is a digital optical audio cable
The digital optical audio cable existed before the arrival of HDMI and is popular among people who have legacy audio systems and equipment. As the name suggests, digital optical audio cables are made of polymer optical fibers to carry audio signals. The signal is transferred via light, which minimizes the risk of electromagnetic interference. Today you will find optical audio cables made from
The use of light also means that optical audio cables have a longer run length than HDMI ARC cables. So if you plan to run these cables inside dry walls, you can do so without worrying about signal loss or degradation.
However, you’ll have to go the traditional route when it comes to connecting a host of peripherals to your TV and soundbar. This means that you will need a separate digital optical cable to transmit audio from your TV to the soundbar.
Like HDMI ARC, they do not support 7.1 channel surround sound. But the good news is that they support up to 5.1 channels.
Digital Optical Cable vs HDMI ARC
If you opt for an optical cable, you will have to go the long way. In this case, HDMI will do the act of transferring the video, while the optical audio cable will transfer the audio. However, if you have multiple devices (Apple TV, a DVD player, and your PlayStation 5) connected to your TV, it will lead to cable clutter.
Unlike the above, you can connect said devices to your TV via HDMI ARC and connect the HDMI cable to the soundbar. And the TV will do the job of transmitting the audio from these devices through the HDMI ARC cable. There, the problems of cable clutter are solved. The only problem is that one HDMI port on the TV will be dedicated to audio
Another advantage is support for HDMI CEC (Consumer Electronics Control). Long story short, HDMI CEC lets you use the same remote to control volume, play/pause or mute connected devices. For example, if your TV is connected to a soundbar, you can use the TV’s remote control to adjust the volume.
However, HDMI ARC is also prone to synchronization issues. On some TVs and soundbars, audio and video are out of sync. And when that happens, things can get boring in the long run.
Contrary to this, digital optical cables offer impressive sound and have minimal risks of audio and video delay/lag.
When it comes to uncompressed or high-resolution audio, neither optical audio cables nor HDMI ARC cables support lossless audio formats such as Dolby Atmos, DTS-HD Master Audio, and Dolby TrueHD. In the case of optical cables, you will have to settle for Dolby Digital and 5.1 channel surround sound.
This is mainly because optical cables lack the bandwidth to transmit high quality Bluetooth codecs like Dolby Digital Plus and Dolby TrueHD. And both of these are integral parts of Dolby Atmos.
On the other hand, HDMI ARC can transmit Dolby Atmos (provided the TV and audio source support HDMI ARC) with only the Dolby Digital Plus audio codec. It gives you the ability to play lossy Dolby Atmos content found on Netflix or Prime Video. However, it cannot handle Dolby Atmos soundtracks in 4K Blu-rays.
what should you do
The answer is in the form of HDMI eARC or Enhanced ARC. eARC, which debuted alongside HDMI 2.1, lets you send high-quality audio from your TV. It has high bandwidth and speed which makes it easy to support 7.1 channel surround sound and high quality codecs like Dolby Atmos, Dolby TrueHD, DTS:X and DTS-HD Master Audio.
Ultimately, the use of a digital optical audio cable and an HDMI ARC cable depends on the compatibility of your devices. Suppose you have a slightly older sound system and you don’t mind missing the high quality sound. In this case, opt for a digital optical audio cable such as the Cable Matters Toslink Cable is almost fine. You’ll have to make do with two remotes though.
On the other hand, an HDMI ARC cable like the PowerBear HDMI Cable is a better choice if your TV and soundbar are compatible. While it can’t give you the full 7.1 channel surround sound, you will get support for Dolby Digital Plus and lossy Dolby Atmos.
However, if your entertainment setup is relatively new, you should look no further than the shiny new HDMI eARC cable. Not only can you enjoy all the Dolby Atmos content on Netflix and HBO Max, but you can also control your TV and soundbar with just one remote.