Sony’s new Master series TVs are the first to feature HDMI eARC, short for enhanced Audio Return Channel, which brings significant benefits in terms of audio support, including Dolby Atmos pass-through.
Enhanced Audio Return Channel
TVs have had the ability to output an audio signal via the HDMI ARC (Audio Return Channel) port for many years. However, the HDMI ARC channel has very limited bandwidth, meaning that it cannot support the latest and greatest audio formats. And often, ARC is even limited to stereo audio.
The new eARC standard promises to fix all of that by increasing audio bandwidth from 2-3 Mb/s, which is best case for ARC, to a 37 Mb/s. That is enough to push through high bitrate and lossless audio (24-bit, Dolby TrueHD etc.). eARC was introduced as part of the HDMI 2.1 standard but as the HDMI Forum confirmed to FlatpanelsHD in January 2018, certain features of HDMI 2.1 can be added to HDMI 2.0 devices via updated firmware.
Sony has confirmed to FlatpanelsHD that the new Master series of TVs, comprising A9F (AF9) OLED and Z9F (ZF9) LCD, will support HDMI eARC, making them the first TV models to do so as far as we are aware.
We asked Sony to shed further light on the matter. In one example, Sony explained how eARC will make it possible for the TV to pass-through Dolby Atmos. What this means is that you can connect an UHD Blu-ray player directly to the TV via HDMI, and then pass-through a Dolby Atmos audio signal (in lossless Dolby TrueHD) to the eARC port from where it can be outputted to a connected soundbar or receiver (needs to support eARC, too). In short, the new Sony TVs will support all of the features that eARC has to offer.
This is a big step forward for TV audio as it also changes the dynamics of how you can set up your speaker system. A soundbar or receiver no longer has to deal with HDMI inputs and all of the video signals from your external players. Of course, a receiver can still serve as the control central in your system but you are probably familiar with the headache of dealing with 4K, HDR, HLG, and Dolby Vision pass-through in receivers.
To be clear, the speakers in Sony’s new Master TVs are not Dolby Atmos-capable and built-in apps such as Amazon and Netflix do not yet have support for Atmos – like Netflix on LG’s 2017 and 2018 OLED TVs. That may change in the future but Sony had nothing to announce at this event. For now, the main benefit of having eARC in Sony’s new TVs is pass-through.
The new Master TVs will not support any other HDMI 2.1 features, the company said.
eARC is the second feature from the upcoming HDMI 2.1 standard to make it into an HDMI 2.0 based TV. Earlier this year, Samsung implemented HDMI VRR (Variable Refresh Rate) and FreeSync in some of its new TVs.
If you want to learn more about eARC then look out for the upcoming article dedicated to the topic.