ARC, or Audio Return Channel, is one of the most useful technologies since the arrival of HDMI itself.
The problem is, most people have no idea it exists, what it’s for, or how to use it. Worse, manufactures rarely explain its advantages, or how their products implement it (if at all).
All about ARC, it’s coolness and quirks, after the jump.
Audio Return Channel is a feature built into the latest versions of HDMI (1.4, and presumably future versions). In its most basic description, ARC sends audio from the TV back down the HDMI cable to something like a soundbar, home theater in a box, and even a few A/V receivers.
Previously, this two-way data transfer only carried handshake info, to tell the source things like “yep, I’m a TV” and “nope, I’m not stealing your content,” or CEC control data. CEC, or Consumer Electronics Control, let you control multiple devices with one remote… in theory and as long as they were connected with HDMI and had the CEC feature. This never worked in reality as well as it did on paper, with cross-brand compatibility being hit or miss. ARC uses aspects of CEC, letting you adjust the volume on a soundbar, for example, with the TV remote. In most ARC products, the soundbar and TV essentially act as one device, with just a single button push to power them both on (no programming required).
The basic ARC functionality, sending audio out of the TV, varies in potential and implementation. On one level, it can send audio from internal TV sources (like the HDTV tuner, or built-in web streaming apps).
On another level, it can send out the audio from other HDMI sources (presumably to a soundbar). In this instance, your TV becomes the central hub, with all sources plugged into it.
This would be the natural way most people, at least those without receivers or HDMI-switching soundbars, would have their systems set up anyway. Adding a soundbar would require no further setup than one new HDMI cable. The TV switches all the sources, and the audio for each one (BD player, cable box, etc), would get sent to a soundbar or HTIB.
The next further level has the TV converting analog audio sources to digital, and sending that to a soundbar. This is less necessary in this digital age, but for those with legacy sources like VHS, this can be useful.
Because there isn’t much consumer awareness about ARC, there isn’t much push on the manufacturer side to hype it. You’ll see mention of it, of course, but hardly ever any details of how it is implemented, and on how many HDMI inputs. Some have ARC on HDMI 1, others have it on HDMI 2. The truth is, it doesn’t matter which HDMI has ARC, as long as you know which one. Many TVs, once you get them out of the box, will identify which HDMI connection has ARC.
How it’s implemented, though, is much harder to determine. According to HDMI Licensing, it is up to the individual manufacturer to choose how to apply ARC. This creates a level of confusion in the market, as it is difficult to determine if the TV only outputs its own sources over ARC, or whether it sends other connected sources as well.
If ARC sounds interesting to you, here’s the quick and dirty: If your TV has ARC already, you’ll just need to get a soundbar, HTIB, or A/V receiver that also has ARC. If you’re getting a new TV, consider ARC as an added bonus, obviously picture quality and screen size are more important. Most mid- and high-end models will likely have ARC at this point. Then it’s just a matter of getting a soundbar/HTIB/receiver with ARC (some do, some don’t).
Setup should happen automatically, with the two devices sensing each other when they’re first connected.
Lastly, the cables
You might need a new HDMI cable for ARC. Older HDMI cables should work, but lots of things should work and don’t. If your cables don’t work, HDMI cables are extremely cheap. Check out our article on the subject, and/or check out Mediabridge or AmazonBasics High-Speed HDMI Cables. Both brands are labeled as ARC compatible.
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