What is HDMI eARC? How it is different from HDMI ARC - Everything You Need to Know to Up The Audio Quality of Your Home Entertainment

There is a lot of confusion prevalent among consumers about the Dolby Atmos compatibility and nuances around the working of Dolby Atmos. 

Most audiophiles, gamers, and movie buffs want their home cinema set-up to pump out quality audio, but get stumped when they have to consider the choice between HDMI ARC (Audio Return Channel) and eARC (Enhanced Audio Return Channel). 

For the uninitiated, eArc is an improved version of ARC. Since it’s the next big thing in revolutionizing audio quality, we decided to present a quick breakdown to you explaining both (while also demystifying a few complex terms). 

Understanding ARC and eARC to take your audio to the next level

In this deep dive, let’s touch base with HDMI ARC first. 

The advent of HDMI ARC has eliminated cable clutter and simplified the user experience in terms of home theatre set-ups and connections. As a user, you get to enjoy high-quality audio from your sound system or TV soundbar with a single HDMI cable. With HDMI ARC the cable sends the audio-visual information not just one way (like in basic HDMI) but also sends audio information back and forth between your source and receiver (for example a TV and a Sound Bar or amplifier/AV receiver).

The HDMI Audio Return Channel (ARC) also makes it easy for TVs to send audio "upstream" to an A/V receiver or soundbar. An easy analogy would be to imagine your TV shaking hands with the audio device, creating a two-fold channel for information.

The most popular benefit of this two way flow of information is that it simplifies the process of controlling devices using a single remote. This is how you can experience effortless control over the soundbar via your television remote. Of course, both the devices in question (the source and the receiving device) need to support HDMI ARC.

However, HDMI ARC does have some limitations as a result of the limited bandwidth available for the signals to travel — it only supports compressed formats which tend to be lossy and with lower-bitrates. Newer formats with high bit-rates like Dolby Atmos signals cannot be processed with this standard. 

The new kid on the block addresses this limitation

To counter this limitation, we have a brand new and improved eARC stepping up that will significantly improve the viewing experience for gamers and movie buffs. The most appealing improvements of the “enhanced” Audio Return Channel are in terms of increased bandwidth and speed. 

This next version of ARC brings in a host of multiple, much-needed features (packed with what HDMI ARC already offers, and many more improvements) while making it easy to operate multiple products, cutting out any extra steps. 

The Enhanced audio return channel (eARC) support provided by HDMI eARC allows support for multi-channel surround sound information like Dolby Atmos, DTS:X, Dolby True HD and more. The higher bandwidth allowed by the HDMI eARC format produces higher video and audio quality. There are other more subtle benefits too including improved video and audio sync even when using multiple devices and smoother auto-selection of transmission formats depending on the support available at the source and the receiver devices. 

To simplify it, Dolby Atmos can be sent over HDMI ARC, but only within Dolby Digital Plus. So, if you have a good streaming plan or a premium atmos package, you would be able to enjoy the best-in-class audio, without worrying about the bandwidth.

All you have to do is simply hook up a compatible soundbar to unwind and enjoy an aural experience alone or go wild, and supersize a house party with friends, and friends of friends.

Here’s a quick summary of the enhanced version of ARC:

• It simplifies connectivity and offers a high level of flexibility
• It offers ease of use 
• Supports the most advanced audio formats (Dolby TrueHD, DTS-HD Master Audio, Dolby Atmos, and DTS:X)
• Packs a punch with the highest audio quality, the best possible audio resolution from your TV

Comparing the HDMI ARC at a glance 

For now, which devices are including eARC? 

• Sony Z9F 2018
• Sony A9F OLED 2018
• Sony X950G 2019
• LG SM9970 8k 2019
• Samsung Q60T QLED 2020
• Samsung TU8000 2020
• LG C9 OLED 2019
• Sony X850G 2019
• LG E9 OLED 2019
• Sony A9G OLED 2019
• LG SM9500 2019
• LG SM9000 2019

Ultimately, it’s a gradual evolution for everyone

HDMI eARC is clearly the evolution of home theatre, and brings significant benefits over previous versions! 

For movie lovers, it delivers lossless audio formats like Dolby TrueHD, which supports up to 7.1 audio channels as well as Dolby Atmos immersive audio for your Home Cinema. 

Since the availability of HDMI eARC devices is still limited, it may be a while before you can upgrade all your devices to this new standard. However, it is a good idea to look for HDMI eARC support in case you are planning to purchase a new TV or receiver anyway, as this would allow you to enjoy its benefits in the future.