Dolby Atmos on TVs: How does it work and how can you listen to Dolby Atmos?

Dolby Atmos on TVs, the object-based surround format with effects that take place not only around you but also above you, becomes more popular. And we see that not only in content, but also on TVs. More and more models are “Atmos compatible”. But what exactly does that mean?

Dolby Atmos: what is it again?

Dolby Atmos is an audio format that is not limited to a number of channels (5.1, 7.1 and so on). With Atmos, any sound can be placed precisely in the room, even above your head.

An important detail: Dolby Atmos is not a codec, but an audio format that coexists with two existing codecs: Dolby Digital + and Dolby TrueHD. The Atmos information is an extension to these two codecs and is hidden in the data stream. An AV receiver soundbar or TV that understands Atmos uses that information. A device that does not know Atmos ignores the extra information and then only uses the Dolby Digital + or Dolby True HD information.

Dolby Atmos offer

“Sounds good,” you think, “Where can I get Atmos content?” Streaming services such as Netflix, Amazon video, Rakuten (only on LG TVs ) and iTunes offer content with Atmos. All these services stream Atmos in a Dolby Digital + format. A second option is Blu-ray and Ultra HD Blu-ray discs. They offer Atmos in a Dolby True HD format.

Dolby Atmos and televisions

We see more and more television models unpacking with Atmos. That is of course a great development. This way you can also enjoy the best sound on your television. Unfortunately, it is not enough to find the word Atmos somewhere in the specifications. After all, there are many different requirements depending on your TV model and set-up.

If you work without an external sound solution, the TV must be able to play Atmos itself. With most 2019 models, this is possible for both Dolby True HD and Dolby Digital +. But there are models that can only handle Dolby Digital + (the 2018/2017 LG models, for example). The overview that we received based on feedback from the manufacturers can be found below:

Can this television play a Dolby Atmos soundtrack without an external sound solution?

(*): For all listed models, this will come via a future firmware update.

Wil your Atmos content via a streaming service, the app of that service must also support that. We asked all manufacturers if their Netflix app supports Atmos, and that turned out to be the case for everyone. Philips did let us know that the Netflix version on their platform does not yet offer Atmos, but it is coming soon.

We immediately say that this setup will rarely deliver fantastic results. The built-in speakers of a television are simply limited in their capacity to deliver a true surround experience, and that also goes for Atmos. The Panasonic GZ2000 has built-in upward-facing speakers, specifically for Atmos effects, so that TV may be an exception.

Dolby Atmos and external sound

A Dolby Atmos compatible soundbar or AV receiver is of course a better solution if you like wish to enjoy truly impressive film sound. But even then there are a lot of possibilities, depending on your source and where / how you connected it exactly, and whether or not your television has eARC.

Option 0: Connect external source to the audio installation

If you use an external source and you have an Atmos compatible audio installation, this is the best solution. Connect the external source via HDMI to your audio installation instead of your TV. That is the preferred situation anyway if you use an AV receiver. But even with an Atmos compatible soundbar, it is best to connect the source device directly to the soundbar. The audio installation can then play your Atmos soundtrack, and send images to the TV. Most Ultra HD Blu-ray players also have two HDMI outputs. This is useful if your AV receiver does not support HDR but does support Atmos. You then connect one HDMI output of the player (which only outputs audio) to the audio installation and the other (which only outputs video) directly to the television.

But what if your Atmos soundbar does not have enough inputs? Then you still have to connect a source to the TV, and use HDMI ARC. Or what if you want to use the streaming apps from the TV? We distinguish three main cases:

Option 1: Internal streaming source

The most common option for people who stream content from, for example, Netflix. In this case you use the Netflix app on the TV. It is connected to your sound solution via HDMI ARC (Audio Return Channel). Because the Dolby Atmos stream from all streaming platforms is invariably packaged in Dolby Digital +, eARC is not required. Dolby Digital + can be sent via a normal ARC connection. This option is universally supported.

Option 1: Internal streaming source controls Atmos in Dolby Digital +

Option 2: External source (Dolby Digital +)

What if you use an external source for your streaming applications? For example an Apple TV or a Blu-ray player that is connected to your television via HDMI? Your soundbar or AV receiver is connected to your TV via a different HDMI cable. In this case the app on your external player must of course support Atmos. If this is the case, the TV must be able to forward that Atmos track via ARC to the sound system. Just like in option 1, eARC is not required, streaming platforms use exclusively Dolby Digital +. We also see universal support for this scenario.

Option 2: External streaming source (connected via HDMI) sends Atmos in Dolby Digital +

Option 3: External source (Dolby TrueHD)

This case deals with an (Ultra HD) Blu-ray player that plays content from an (Ultra HD) Blu-ray disc.

The player is connected to your television via HDMI. Your soundbar or AV receiver is connected to your TV via a different HDMI cable. If the disc contains an Atmos track in Dolby Digital +, then you fall under option 2. But what if you want to play an Atmos track in Dolby TrueHD? Dolby TrueHD cannot be transmitted via ARC, but can be transmitted via HDMI eARC. If your TV and your sound solution support this, there is no problem. But what if your television does not have an eARC? Then there is another possibility. Some models can convert the incoming Dolby TrueHD track to a Dolby Digital + track (of course with Atmos) and that can be passed on via ARC. Here the chosen option varies with the manufacturers. Some models offer eARC (LG, some Sony and some Samsung), others can convert the TrueHD stream (Panasonic, Philips, some Sony)

Option 3: External streaming source (connected via HDMI) sends Atmos in Dolby TrueHD

(*): eARC is coming for all listed models via a future firmware update.

Conclusion

Dolby Atmos adorns a lot of televisions, but unfortunately it doesn’t always mean the same thing. Some models can play the Atmos track themselves, others are “Atmos compatible” and can only transmit an Atmos track to an external audio installation, and others can both. In addition, other factors play a role, depending on your source and setup, such as the possible presence of eARC. Whoever is in the market for a new television and wants Atmos, takes this important conclusion to heart: inform yourself clearly about the possibilities of your new television. And consider in advance which source you wish to use, whether you work with an external audio solution and how you connect everything together. If streaming apps are your only source, the chance that your setup works is greatest. If you work with (Ultra HD) Blu-ray discs, you will have to search for a television with eARC or transcoding depending on the setup. In any case, the easiest solution is to connect your source directly to an external audio installation. The result will be much more impressive than if you trust the built-in speakers of the TV.