With more and more complex computers in the home, it is normal for everyone to increase the number of options with which to exchange content. A device cannot be designed in isolation at home, because integration into the smart home makes the interconnection between all the equipment as common as necessary in many cases.

Wireless connectivity, either with Wi-Fi in one of its versions, using a central hub or using Bluetooth. And also the physical connection, wired, like all life. And if before buying a television, DVD or video was to check if it had a SCART, today the picture is much more complex. A list of connections whose latest arrival has a name: HDMI eARC.

Prepared for the highest demands

By HDMI eARC we mean an improved version of ARC (Audio Return Channel), its name in English. Coming from a consortium of companies that promotes the development of the HDMI interface (Sony, Toshiba, Hitachi, Philips, Panasonic …), what HDMI eARC offers is that televisions and devices that include can send any current high resolution format of multi-channel digital audio to the audio system that we have paired with the TV.

Whether it’s a sound bar, home theater system, A / V receiver, or any other compatible device, eARC HDMI content can be sent with Dolby TrueHD, Dolby Atmos, DTS Master and DTS: X, the highest quality sound formats on the market. More and more brands are betting on this improvement and there we have the boxes for example LG, TCL, Sony …

Enhanced ARC can extract Dolby Atmos and DTS: X audio from any of the TV’s HDMI ports to send to an A / V receiver or sound bar

The advantages offered by HDMI eARC are possible thanks to the increased transfer speed that the arrival of the HDMI 2.1 standard brought, as well as the new protocol used in the process of video and audio synchronization. In this sense, it will be essential to know what type of HDMI connector on our television (1.4, 2.0 or 2.1) for which we have no other choice but to consult the user manual.

In this sense, the ARC protocol contained in the HDMI 1.4 and 2.0 specifications only allows PCM, Dolby Digital and DTS audio to be sent. Thus, higher quality formats such as Dolby TrueHD, DTS-HD Master Audio, Dolby Atmos and DTS: X are left out for the support of HDMI 2.1 and eARC. As a reminder, although in theory eARC is only compatible with HDMI 2.1 because it is a feature linked to the latter standard, some high-end televisions with HDMI 2.0 offer it on some of their connectors.

A palpable difference

The difference with ARC is that in this case we limit ourselves to using a maximum of 2 PCM audio channels with bitrates of 1 Mbps: the result is that we will only have access to two stereo channels or the maximum 5.1 compressed audio. With HDMI eARC, the transfer rate is extended to over 37 Mbps and thus uncompressed multichannel audio tracks of up to 8 channels at 192 KHz and 24 bit are supported.

With HDMI eARC, we will have access to Dolby Atmos and DTS X formats as well as conventional versions of 7.1 channels and lower. Plus, it ends with one annoyance that we’ve all surely experienced at some point and are those lip sync failures present in ARC.

EIAJ-TOSLINK OUTPUT (DIGITAL OPTICAL)

HDMI ARC

HDMI (ARC ENHANCED)

Cable type

Optical fiber

HDMI

High Speed ​​HDMI with Ethernet Ultra High Speed ​​HDMI

Stereo sound

YES

YES

YES

5.1 compressed sound

YES

YES

YES

Uncompressed 5.1 sound

NOT

NOT

YES

7.1 uncompressed audio

NOT

NOT

YES

Supports object-based audio such as DTS: X and Dolby Atmos

NOT

NOT

YES

Maximum transfer rate

384 Kbit / s

1 Mbps

37 Mbps

Visibility of control protocols

NOT

CCE

EARC data channel

HDMI eARC Compliant

NOT

NOT

YES

Correction of lip sync

NOT

Optional

Obligatory

Volume control and mute

NOT

YES (CEC)

YES (CEC)

If we connect the TV and use the HDMI eARC connection, all types of content will benefit, whether using the physical format for example on a console, through a video streaming platform, with DVB-T HD content. and therefore with any source that we have connected to our TV.

On paper, some outrageous specifications but we must take into account a fundamental aspect and that is that in order to take advantage of all these improvements, it is necessary that all the devices that we have interconnected are compatible with HDMI 2.1 and eARC.