HDMI eARC vs ARC

Have you ever noticed the "HDMI ARC" or "eARC" ports on the back of your smart TV or other media player? These ports can connect your TV to a sound bar or A/V receiver to achieve cinematic surround sound. However, facing the two technical standards of ARC and eARC, many non-professional users often find it difficult to choose when building a home audio-visual system - which interface can unleash the full audio potential of the device? Through the analysis of this article, you will clearly understand the differences between the two features and quickly find the connection solution that suits you best. 

What is HDMI ARC?

HDMI Audio Return Channel (HDMI ARC) was first introduced in 2009 with HDMI 1.4, which means that an HDMI port can be used as both an input for audio and video, and as an output port for audio. Previously, a separate audio cable was required to connect a TV to an audio device (such as an AV simplifyer and soundbar). Now with ARC, you can reduce the number of audio cables and simplify your AV system. ARC simplifies the connection between the TV and audio system by enabling bidirectional audio signals using a single HDMI cable. It supports many audio formats, including PCM, Dolby Digital, Dolby TrueHD, DST, and DTS-HD Master Audio. ARC also supports remote control of the power and volume of audio devices via HDMI CEC. An HDMI cable can connect game consoles, TVs, and Blu-ray players to an audio device (soundbar or AV receiver) for the best sound experience.

What is HDMI eARC?

HDMI eARC stands for "enhanced Audio Return Channel" and was first introduced in 2017 with the HDMI 2.1 standard. It has all the features of HDMI ARC and has been significantly improved, providing higher bandwidth and speed, and supporting new formats.

HDMI eARC supports 32 channels of uncompressed audio at up to 37 Mbps. It supports uncompressed 5.1 and 7.1 audio, and can handle advanced audio formats such as Dolby TrueHD, DTS-HD Master Audio, Dolby Atmos, and DTS:X. This not only brings an unparalleled audio experience, but also allows you to enjoy 4K Blu-ray and streaming video.

In addition, HDMI eARC enables smooth communication between different devices without activating HDMI CEC. It ensures high-quality audio signals to enhance your audio experience and simplify audio setup.

Comparison between ARC and eARC

Which is better, ARC or eARC?

eARC is an advanced version of ARC, making it a better choice to use. One of the significant differences is that eARC has a higher speed of up to 37Mbits/sec, compared to ARC's approximately 1Mbits/sec. Therefore, if you want fast HDMI, then eARC is the first choice. In addition, eARC also has a higher bandwidth, allowing more audio channels to be transmitted, and the quality of the sound signal is higher compared to ARC.

Another big advantage of HDMI eARC is its compatibility with object-based audio formats, allowing it to be used on Dolby Atmos and DTS:X. In addition, using an HDMI eARC cable has an advantage because it has ARC fallback. This means that you can connect eARC to any device that does not support it but supports ARC.

How do I know if my HDMI cable is eARC?

No HDMI cable is specifically rated for eARC, but HDMI eARC is only fully supported by HDMI 2.1 cables, so if your cable is an HDMI 2.1 cable, then it should support eARC without a problem.

However, if you don’t know what HDMI version your cable is, it can be a little tricky to find out. Some HDMI cables have labels to tell you their version, so look out for those. Some also have a resolution printed on them, such as 4K, or 8K. In the case of 8K, chances are you have an HDMI 2.1 cable, in which case it should support eARC as long as you connect it to a compatible display and device.

The only way to know for sure if you have a cable that is compatible with eARC is to test it. If you plug your unknown HDMI cable into a TV and device that can support 4K resolution and up to 120Hz refresh rates, then simply setting the TV to different settings will confirm your HDMI cable’s generation. If it can only manage 4K at 30Hz or less, it’s HDMI 1.4. If it can manage up to 60Hz, but no more, it’s HDMI 2.0, and if it can manage the full 4K 120Hz, then it is HDMI 2.1 and compatible with eARC.