How to use Digital Optical cable?

If you’re the owner of a newer HDTV, A/V receiver, sound bar, or home theater in a box (HTIB), you may have noticed (then promptly forgotten) a little symbol on one of the device’s HDMI inputs that says “ARC.” What does this mean? Hint: it has nothing to do with the reactor that powers Ironman’s suits.

ARC, in this case, stands for Audio Return Channel, which is a little-understood protocol that started showing up on select HDMI-equipped devices a few years back. Today, it is increasingly common. The technology is especially useful and has the potential to significantly simplify home entertainment systems. The problem is, few know it even exists, much less what it can do. Here, we’ll go over the basics of ARC so you can put its mythical powers to work for you.

But first, a quick refresher on HDMI itself.

HDMI: the basics

HDMI, which stands for High Definition Multimedia Interface just celebrated its 10th birthday this month. You probably use it now, but you may not know how cool it actually is. The system was created as a faster, more efficient way to deliver high quality digital video and audio to and from consumer electronic devices. Though many people use HDMI strictly as a means for connecting Blu-ray players and game consoles to their TV, it can do much more.

Besides transferring both video and audio in a single feed, HDMI was also designed to carry what the industry refers to as “handshake” information from one device to another. These shared transmissions were originally intended to communicate basic data for preventing content theft, as well as messages like the status and type of component connected.

But the system was also designed to share more complex messages as a part of what’s called Consumer Electronics Control (CEC). CEC allows for a single remote to control features on up to 15 connected devices. There are virtually as many names for CEC as there are electronics brands: Samsung calls it “Anynet +, ” for instance. Unfortunately, the system has never really lived up to its potential, and is often mistranslated or simply lost between components from different manufacturers. Until ARC.

The power of ARC

ARC can simplify your home theater system in two important ways. The first, and perhaps most useful feature that ARC brings to the table is the aforementioned organization of CEC for single remote command.

The most common employment of single remote command would be for users who have supplemented the shameful audio of their flat screens with a sound bar, sound platform, HTIB, or other secondary audio device. As long as both devices are equipped with ARC, simply connecting the component to the TV’s ARC HDMI port will allow for control of power, volume, and other features from your TV remote. In most cases, it will also simply transfer your TV audio to the unit automatically, without having to deactivate the TV’s on-board speakers.

This feature is extremely useful for those who use their TV as the hub of the entertainment system, meaning gaming consoles, Blu-ray players, set-top boxes, and other devices are all connected to the TV, and sound is then passed to the supplemental audio device. It allows for significantly better audio performance for all of your content than what you’ll get from a TV alone, but without having to think about the audio device.

In through the out door

The other important function ARC performs is sending signals both “upstream” and “downstream” over a single connection, meaning signals can travel in and out of a device over a single ARC HDMI port and cable. “Downstream” refers to signal that is being passed from the source, say a Blu-ray player, “down” to another device. “Upstream” would then mean sending signal the opposite way over the same cable. Why is that necessary? Convenience.

The most common use of HDMI ARC will be among owners of new sound bars or sound platforms. ARC allows you to connect all of your sources, (BLu-ray, Cable Box, game console, etc. ) to your television and bounce the audio signal out to a sound bar via an ARC HDMI port. This way, the TV is the hub and only one remote control is needed.

For those who use an Audio/Video (A/V) receiver as a hub instead of their TV, ARC can still simplify cable connections a little. While audio from various sources is going directly to an A/V receiver in this kind of setup, any audio coming from the TV still needs to get to the receiver somehow. For instance, let’s say that the television is the preferred smart device in the bunch. Any audio from Netflix, Hulu plus, etc., will only play out of the TV unless it is sent to the receiver somehow. In the past, this would have required another cable, usually an optical digital cable. But with HDMI ARC, audio can be sent back down to the receiver through the same cable that already connects the two devices. For those with wall-mounted TVs, that’s one less cable to snake through the wall!