All about soundbars: Dolby Atmos, HDMI-eARC and more

Buy sound bar

Basically, all soundbars are the same: a long device containing small speakers or drivers that play the different sound channels of a movie soundtrack. Yet there are definitely things to pay attention to if you are considering buying such a soundbar. Then you suddenly come into contact with all kinds of terms such as Dolby Atmos, DMI-eARC and more properties. What do you need to know about that?

If you delve into the range of soundbars, you will soon discover that there are many different models. You also notice the price that one soundbar is not the other. For a soundbar, prices start around 150 euros and end around 2000 euros.

Where does that huge split come from? Things like streaming options, design and power play a role, but perhaps the most important factor is the surround experience offered.

Why a soundbar

When do you need a soundbar? A soundbar can be a solution to a real problem, such as speech that is not well intelligible. This problem rarely occurs on a quiet talk show. In a movie, where there are many other sound effects or music playing, those small TV speakers can get overwhelmed.

You may also be longing for a more immersive viewing experience. George Lucas once remarked: sound and image are equally important to get you into a movie, so that you really get into it. A nice, large screen is not enough. Support the images with surround sound and you get much more immersion.

Of course, this also applies to gaming, where surround sound or positional audio not only provides atmosphere, but also provides tactical information. In a battle royale game, those gunshots in the distance can lead you to an opponent’s trail.

Sound from the TV itself

Is the sound that comes out of televisions really that bad? The answer to that question was ‘yes’ for a long time, but it is now a bit more nuanced. With the absolute top models among televisions, you can now count on much better audio performance.

Some TV manufacturers have even partnered with hi-fi brands to deliver better sound. This is partly a marketing ploy, but the collaboration between Philips and Bowers & Wilkins, among other things, yields really good results. As you can read in this Philips 65OLED936/12 review.

Unfortunately, such good audio performance is only available with television sets costing thousands of euros. The majority of budget and mid-range televisions continue to be equipped with small speakers that are unable to reproduce the full frequency range.

Soundbar with Dolby Atmos

The hype term of 2021 is without a doubt Dolby Atmos. Most soundbars feature this surround technology that complements the classic surround channels at ear height with speakers positioned higher. Or, in the case of soundbars, speakers that face upwards and allow sound to bounce off the ceiling. Thanks to these so-called height channels, sound effects can be positioned both in width and height.

That is positive for two reasons. For starters, you get more realistic sound effects. Helicopters fly over you seamlessly, instead of suddenly jumping from in front of you to behind you. You notice that immediately.

More subtly, those height channels represent the ambiance or spatial audio. A scene in a tiled bathroom, a busy shopping street or a large cathedral therefore sounds more natural and realistic. This is also the added value with films and TV series that are not packed with spectacular scenes. It still makes a Scandinavian crime or a historical drama more real.

5.1.2, 3.1, 7.1.4…

With soundbars you often get a series of numbers with dots in between them. You can immediately see whether a soundbar is ready for Atmos. For example, a conventional surround setup is 5.1. That’s five channels at ear height (left-center-right-left rear-right rear) plus one subwoofer (LFE or Low Frequency Effects).

Add two Atmos channels and you get 5.1.2. Other setups are possible, such as 2.0 (stereo), 3.1 (stereo plus a center channel for dialogues and a subwoofer) or 7.1.4.

These numbers represent a surround setup for channels that come from separate speakers. That is not always the case with a soundbar. Thanks to complex algorithms, speakers can take on multiple roles, so that a soundbar with only three speakers would still deliver Atmos.

It is quite impressive how software can focus sound, including by intervening on the phase, but the result with these (cheaper) Atmos soundbars remains behind devices with separate speakers per channel.

Dolby Atmos is a technology that has been brought to the consumer from the cinema. Inevitably, something has been lost. You simply cannot replace 64 speakers controlled by smart processors with a few small speakers in the front of the room.

It is possible to get a good Atmos experience at home, but then you have to go for a surround setup or a high-end soundbar with separate wireless speakers that you place next to and behind your seat. Usually, those separate speakers will only reproduce the rear channels, not the two Atmos channels. Samsung is about the only one to offer a soundbar with dual satellite speakers.

Most soundbars offer an approach to Atmos rather than an accurate representation. That’s not necessarily a bad thing. By emphasizing an impressive experience, you do get an immersive immersion in a movie or game. And that’s what it’s all about.

What is HDMI eARC?

New TVs and soundbars feature HDMI-eARC. This is a new version of HDMI-ARC, a standard for transferring sound from the TV to an audio device. “Logical”, you may think, but audio actually goes ‘against the current’ at that moment. After all, HDMI was originally designed to bring image and sound to the television, not the other way around. It wasn’t until the soundbar was invented that there was a need for an audio channel that worked in the other direction.

eARC does the same, but using a different technique, so that surround sound in the highest quality (found on Ultra-HD Blu-rays) can also be transferred. In practice this is not so important. HDMI-eARC also offers better lip-syncing.

With HDMI-eARC, TV builders are taking into account a new reality: streaming is now the most important thing, TV decoders and disc players are being dumped en masse. That is a big change. In the past, it was also the case that it was best to connect a video source (such as a console or Blu-ray player) to your audio device. That provided the best audio quality.

Thanks to eARC, that is no longer the case. It is now common practice to link your sources directly to your television. In addition, many watch on their television via the apps. In short, there is little demand for extra HDMI inputs on a soundbar. You’ll even see high-end models without an extra HDMI port.

This does create a problem for those with an older TV who want to experience Dolby Atmos. Devices built before circa 2017 rarely offer Atmos via Netflix, Disney+ and other streaming providers. The necessary apps may be there, but only provide Dolby Digital Plus 5.1 on those older devices.

Even if you connect a modern source, such as an Apple TV 4K or Xbox, to your older TV, you still have a problem. The television will not forward the Atmos stream that the Apple TV provides to the soundbar. The audio is then converted to stereo. The only option you have in that case is to link your source directly to the audio device. But if there is no extra HDMI input on the soundbar, you can’t.

If you have a new television, possibly equipped with HDMI-eARC, the TV apps may be able to deliver Atmos and the audio from a source that is connected to a television is fully forwarded (passthrough).

Sound calibration for sound bars

Sound is a very curious thing. No matter how good your soundbar may be, it can still sound bad if you install it at home. That’s because the room can be a disruptive influence. The type of floor, the height of the ceiling and even the shape can amplify or attenuate certain frequencies.

Fortunately, the sound signal can be digitally adjusted to compensate for the specific acoustic problems in your living room. This is possible via room calibration, a valuable function that you find on more and more soundbars.

Calibration means that you play test tones once to ‘measure’ the room, after which the sound is adjusted. Usually it’s just a matter of tapping something in a soundbar’s app and waiting a minute or two.

Stream music on soundbar

Several soundbars in this file have their own apps with which you can play your own music or streamed music. Nice, but many people prefer to work with their trusted music apps.

This is possible with most models via Chromecast and/or AirPlay 2. The first technology comes from Google, the second from Apple, and many soundbars have both on board. They offer pretty much the same thing: you can just tap an icon in a service app to play the music through the soundbar.

The big advantage of Chromecast is that the music stream runs directly to the soundbar, without draining the smartphone battery. You can even choose a playlist and then shut down your phone and the music will continue to play. AirPlay is more versatile and lets you send audio from a YouTube video or a game to a soundbar, for example.

AirPlay 2 and Chromecast both support grouping different speakers. For example, you can play the same track synchronously on your soundbar and a Chromecast or AirPlay 2 speaker in the kitchen. Conveniently, Chromecast and AirPlay make it easy to connect a soundbar to the WiFi network. Via the Google Home app or the wifi settings from an iPhone or iPad you can arrange this with a few taps.

Thanks to Spotify Connect, Spotify users can see their soundbar (if it is connected to the network) just popping up in the Spotify app itself. This works very well and this function is now available on almost every soundbar with WiFi.

You cannot forward your TV sound with Chromecast or AirPlay 2. For that you need a real multiroom soundbar, such as from Denon, Sonos or Bluesound. The software platform is central to their products and there is more flexibility to transmit sound to other devices elsewhere in the home. For example, you can also connect a record player to an auxiliary input of the soundbar and listen to the sound through a speaker in the dining room.


Recent Articles

Related Stories