What your TV's eARC HDMI port actually does

Summary

eARC is an HDMI-based connection standard for home theater audio.
To use eARC, your TV, cable, and audio device all have to support HDMI 2.1.
eARC is backwards compatible with ARC, but limited by ARC’s reduced bandwidth.

Let’s face it — unless you’re experienced, it can be needlessly complicated to sort out a new home theater setup. No new TV comes with a pamphlet explaining all the various industry standards, much less which ones are necessary to use in your circumstances. It’s assumed that you’ll figure these things out while you’re shopping, and then again when you unbox everything in the living room.

Case in point: eARC HDMI ports. They’re something you’ll see on the back of most modern TVs, as well as a number of speakers and receivers. But what do they handle, exactly? And is there any special advantage over ARC, which is more universal? I’ll explain everything you need to know before you start streaming and gaming.

Should you get a handheld or a laptop for portable PC gaming?

You might not need a laptop as much as you think you do.

What is eARC?

The latest in TV audio

eARC stands for Enhanced Audio Return Channel. It’s an HDMI-based alternative to traditional audio standards like 3.5mm or optical, and an upgrade from its predecessor in the HDMI space, ARC. It’s mostly aimed at home theater setups, helping to connect compatible speakers, receivers, and all-in-one soundbars, such as the Sonos Arc.

The key advantage of eARC is bandwidth. Though ARC and optical can technically handle 5.1-channel surround sound, and ARC even supports 3D surround formats like Dolby Atmos, neither of those connection types can handle surround sound in full fidelity. eARC uses a 37Mbps pipeline to deliver uncompressed, 192kHz, 24-bit quality. eARC tends to be compatible with more formats as a result, and it’s simply unavoidable if you want to build a 7.1-channel system.

The key advantage of eARC is bandwidth.

There are some additional perks. Whereas lip sync is optional with ARC, and non-existent for optical, it’s a mandatory part of the eARC specification. That’s not to say optical speakers will automatically fall out of sync — there’s just a chance of that happening in some circumstances.

eARC also uses its own input discovery and identification system, separate from the CEC technology TVs otherwise rely on. This shouldn’t matter much in practice, particularly since eARC speakers still depend on CEC for things like volume control and powering on.

8K gaming isn’t worth the effort yet

It’ll be the norm one day, but that day is years off.

What do you need to use eARC?

You might be in for some sticker shock

The TCL Q85H soundbar in a living room with blue graphics showing the surround sound.

TCL

At a minimum, eARC requires that both an audio device and its connected HDMI port support HDMI 2.1. If you’re unsure, check your audio gear’s specifications, and connect it to the port marked “eARC” on your TV. If you don’t see an eARC label, you’ll have to check your TV’s spec sheet, since some HDMI ports might only be equipped with 2.0.

You’ll also need an HDMI 2.1 cable, preferably one labeled “Ultra High Speed.” Cables marked “Standard HDMI Cable with Ethernet” or “High Speed HDMI Cable with Ethernet” will also work, but don’t support as many video resolutions as Ultra High Speed, which could be important depending on what you’re connecting.

Every other device you want to take advantage of eARC — such as a game console or media streamer — should be connected via HDMI 2.1 as well. You’ll still get audio if a peripheral is connected through HDMI 2.0, but quality and format support may be stepped down.

A Steam-Deck OLED connected to a Hisense U6N TV.

How to turn a Steam Deck into a TV gaming console

You can play PC games on your TV without buying a desktop or laptop.

Is eARC backwards-compatible with ARC speakers?

Insert giant asterisk here

Yes, technically speaking. That’s because ARC has been around since the HDMI 1.4 specification, which first emerged in mid-2009 — an eternity in the tech industry. Any ARC speaker you plug into an eARC port will still produce audio, and depending on what you’re watching or listening to, you might not notice the difference. You won’t even need an HDMI 2.1 cable.

The catch, as you’d expect, is that ARC is a bottleneck. ARC bandwidth is capped at 1Mbps, so any surround sound you pump through it has to be compressed. Stereo tracks are unaffected.