Explained: What are 4K, HDR, and Dolby Atmos?

Getting With the Times

The Apple TV does not get updated often and for good reason: its job is simply to bring your TV into the digital Apple garden. As long as you can watch what you’ve bought or have access to streaming services, there’s no real reason to buy something new while it all works. That doesn’t mean there isn’t some point in time where the new Apple TV model has enough improvements to make it worth it for owners of ANY model to upgrade.

The new Apple TV 4K is just such a model. If you aren’t sure where your current model of Apple TV falls in the spectrum, pop over to my Apple TV generation guide to figure out which one you currently have, as well as a bit of upgrade advice.

Whether you’re already looking at getting the latest Apple TV model or not, this article deals with the three main features that are being used to sell the latest and greatest Apple box. Specifically – 4K, HDR, and Dolby Atmos. If you have no idea whether these three features are worth it or not, read on for a simple explanation of each.

The 4K Advantage

The simplest of the three features to explain is 4K, since it’s just an evolution of HD TV. Basically, a video with a “4K” resolution has around four times as much detail as a Full HD one. Full HD video consists of a pixel grid measuring 1920 x 1080 pixels. That’s around two million pixels. While there are minor variations, the standard 4K resolution is 3840 x 2160, which comes to almost 8.3 million pixels. That’s approximately four times the resolution of Full HD and so the name “4K” stuck.

The Apple TV can play back video at this resolution without breaking a sweat. You’ll find plenty of 4K content to watch as well. Most new streaming shows from providers like Netflix and Amazon Prime Video are done at 4K resolution, and you can buy or rent 4K movies and shows directly from Apple as well.

Of course, the Apple 4K TV alone isn’t enough to enjoy the benefits of 4K. You obviously need a TV that has a panel that can display that many pixels. Playing a 4K image on a Full HD TV offers no benefits at all. If you are going to stream 4K content, you also need a pretty fast internet connection. For example, Netflix officially requires at least a 25 Mbps connection to play their 4K content, although in my own experience you can get away with half of that if no one else is using the connection. You also need to subscribe to the 4K package with some providers.

The good news is that 4K TVs, even OLED 4K TVs, are now much more affordable than before. So upgrading might not be as expensive as you think. You should, however, take your room size into account, as well as how far away from the screen you’ll sit. There are guides on the net, usually from TV makers, that help you figure out whether you’ll even see a difference with 4K in your room setup.

HDR Has a Bright Future

4K is nice under the right circumstances, but most people aren’t going to really notice the impact of 4K without putting the images side-by-side. HDR, on the other hand, grabs you by the eyeballs and makes sure you notice it.

HDR is essentially a technology that dramatically widens the contrast, color, and brightness ranges of standard television. There are various HDR standards; some cheaper HDR TVs are only technically allowed to use that term. So before you buy your new TV, look for a review that tests whether it actually conforms to the minimum standards for good HDR.

You also need HDR content to play on that TV, but just as with 4K almost everything made by big studios these days supports HDR. 4K and HDR are almost always present together. That being said, Full HD HDR TVs do exist, although I have personally never seen one. So even if 4K isn’t of much benefit to you, HDR really is a big deal and almost never comes on anything but 4K sets. Once you’ve seen the vivid power of HDR, it’s incredibly hard to go back to comparatively dull and lifeless non-HDR content.

The Sound of Atmos

Dolby Atmos is another big-ticket technology supported by the new Apple TV. While we have had HD video standards for the longest time, the same hasn’t been quite true for audio. The old multi-channel audio standards are still in use, but they aren’t exactly as high-fidelity as their video counterparts. One of the issues is that the popular optical audio cable doesn’t have enough bandwidth to carry the audio at a good enough quality anymore. So HDMI is carrying all the data and then passing it on to your receiver. It’s also worth noting that multi-speaker surround systems aren’t that popular anymore. People tend to opt for the more elegant sound-bar with pseudo-surround projection or the (often bad) built-in speakers in their TV sets.

So in comes Dolby Atmos. It was first introduced in 2012 as the next standard in audio, but Dolby had a hard fight to get everyone else on board as well. Now Dolby Atmos is starting to gain some real traction. Even high-end smartphones now come with Atmos certification, although it doesn’t mean much when listening to sound through the tinny phone speakers!

What makes Atmos special is how it treats spatial audio.The old surround-sound method had the content creators make a track for each channel. So if you had a 7.1 surround system the audio from each speaker is predetermined. With Atmos you have virtual sound objects, which can be dynamically tracked across a large number of speakers in almost any configuration. This means if you play Atmos content on your new Apple TV and connect it to a good Atmos sound system, you’re in for a true next-generation experience.

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