HDMI 2.0 and its new brother HDMI 2.0b are still the most common versions of the HDMI standard, but as of 2020, its market share will begin to decrease, as the industry gives way to the latest and best version: HDMI 2.1.
But because HDMI 2.1 is still very new and the number of devices that support it are very few, you probably have many questions. Maybe you worry if your new 4K TV, media player or Blu-ray 4K Ultra HD player doesn't work? Or maybe you are worried that you should buy a lot of new HDMI cables? And then come the deepest questions about HDMI 2.1: What does it do and why do I need it?
We have all the answers here, and while the topic is a bit technical, we have done our best to explain it in a simple way.
Is my new TV about to become obsolete?
Definitely not. If your TV supports 4K UHD resolution and HDR (High Dynamic Range, for its acronym in English), or even 4K only, it is far from obsolete.
If you bought your TV in recent years, then you should not worry about a good time.
It is true that HDMI 2.1 opens a lot of new possibilities, which we will address shortly, but the full benefits of these features will not be realized for many years. The changes are exciting, but it will take a few more years until specifications like the resolution of TV 8K and 4K at 120 Hz are more common.
If I am thinking of buying a new TV, should I wait?
In the past, our advice was: "No, go ahead and buy a new 4K TV with confidence." It was still a long time before HDMI 2.1 arrived. But CES 2020 has changed our opinion. We saw a lot of new TVs in Las Vegas and, although they didn't offer revolutionary features, they all had two things in common: better image quality and compatibility with HDMI 2.1. Well, all except Sony, which seems to stay with HDMI 2.0b for now.
Does HDMI 2.1 require new HDMI cables to function properly?
S. As you can see later in the technical explanation oriented to the specifications of HDMI 2.1, the new standard almost triples the amount of data that can be transmitted on an HDMI cable. That being the case, to take full advantage of HDMI 2.1, the use of a new certified ultra-high speed HDMI cable will be required.
Note: Nothing changes with respect to the size or type of connection of the HDMI cable ports and connectors. The new ultra-high speed HDMI cables will still fit perfectly in older devices.
Is HDMI 2.1 compatible with previous versions?
S. You can connect any device designed for HDMI that is compatible with any previous version of the HDMI standard, and work well on a new TV or screen designed for HDMI 2.1. Ultra high speed HDMI cables are also compatible with previous versions. For example, if in the future you want to connect your then archaic Xbox One to your shiny new 8K TV with HDMI 2.1, that is not a problem at all.
Why do we need a new HDMI version?
Home entertainment devices are already approaching a bandwidth of 18 Gbps that supports HDMI 2.0b. For example, if you take a 4K Ultra HD Blu-ray disc, the 4K image resolution alone is a large bandwidth. But if you also add 10-bit color, 4: 4: 4 color sampling, 60 fps content, Dolby Atmos, DTS and HDR, you approach the maximum limit of 18 Gbps.
What does HDMI 2.1 do that HDMI 2.0b does not do? What's new
As seen so far, HDMI 2.1 can handle much more information, and therefore, it is easy to understand why it provides higher video resolutions such as 8K or even 10K. But high resolution capability is the least exciting part of HDMI 2.1 in our opinion.
HDMI 2.1 allows higher resolutions at higher frame rates than before. With HDMI 2.0b we can enjoy a maximum resolution of 4K at a maximum frame rate of 60Hz. With HDMI 2.1, we can get 4K at 120Hz, 8K at 60Hz and a resolution of up to 10K for industrial and commercial applications. Increasing the resolution is not a big problem alone for televisions and projectors: we are already close to maximizing the limit of detail that our eyes can see at typical viewing distances, but adding higher frame rates is great news for the gamers. Higher frame rates mean smoother and better looking games. The HDMI organization says that some Hollywood directors are eager to migrate to a 120Hz native film and want that high-speed frame content to reach viewers' homes, as well as cinemas.
Enhanced Audio Return Channel (eARC). The Audio Return Channel (ARC) is an HDMI 2.0b function that allows audio to move back and forth through an HDMI cable between a TV and an A / V receiver or soundbar. Unfortunately, the limited bandwidth of HDMI 2.0b often compresses the audio and is reduced to stereo. With the Enhanced Audio Return Channel (eARC), we can now get uncompressed and full resolution audio through HDMI 2.1 connections. Dolby Atmos is a perfect example. With ARC, Atmos only works when using Dolby Digital Plus, a compressed audio signal. eARC allows Dolby Atmos to deliver its best performance using Dolby TrueHD, a high resolution audio signal without loss.
This dramatically simplifies the system settings because it means that users can connect everything to their TV and then connect a single HDMI cable to their receiver or soundbar without losing sound quality. Less cables, less mess and better sound!
The High Dynamic Range is an evolution for TV image quality from 1080p HD, but it can be better. If you are familiar with the Dolby version of HDR, Dolby Vision, you probably know that the reason why some experts consider it superior to other formats is that it is a dynamic HDR medium. In other words, Dolby Vision makes changes to the configuration of an image as the image changes. The result is a more accurate, vibrant and … well, dynamic image.
The only problem with Dolby Vision is that it is a patented technology and not all manufacturers of electronic products want to pay license fees to use it. HDMI 2.1 brings the dynamic performance of HDR to other flavors, including the dynamic version of HDR10, known as HDR10 + and others, that should provide better HDR experiences to more TVs and more formats.