If you’re in the market for an above-entry-level soundbar right now, you’ve probably noticed the Dolby Atmos logo that’s almost always present on the box. This reassures most of us and leads us to assume that, once we take our new speaker home, whatever Netflix or a 4K Blu-ray sends out will be completely in its wheelhouse. It rarely works like that, though.

At least three gatekeepers sit between you and your best audio (or between the source and the soundbar): the audio format, the HDMI connection, and the TV in the middle. Any of them can swap a lossless track for a compressed one, or a surround sound mix for plain stereo, without letting you know. Even if you follow the rules for setting up a soundbar with your TV to the letter, it won’t save you, and as we’ve covered before, your TV could be ruining what you get out of your top-notch speakers in ways you don’t even know about.

The good news is that most of the damage is fixable, and, in this arena, knowledge is power.

Dolby Atmos isn’t one-size-fits-all

Though streaming only ever sends you the smaller size

Credit: Dolby

The Dolby Atmos sticker on the soundbar box refers to the positional layer (the metadata that gives the sound texture rather than just making it loud), not the audio underneath it. For streaming services, Atmos comes in with Dolby Digital Plus, a lossy codec that strips away detail to keep file sizes manageable. On a 4K Blu-ray disc, meanwhile, Atmos is carried by Dolby TrueHD, which is lossless but still compressed for storage purposes.

That may sound like a bad deal, but a well-mixed Dolby Digital Plus track isn’t exactly something to feel hard done by about. It does, however, prove you’re not hearing things, and the same movie really will sound better on Blu-ray than on Netflix.

As such, if you only watch movies and shows on streaming, you shouldn’t worry too much about TrueHD. Instead, focus on the handful of settings that make streamed Atmos behave properly. Some of these, as we’ve covered, can actually feel like a free upgrade for your setup.

Remember, ARC and eARC aren’t the same

Despite looking and sounding extremely similar, ARC and eARC are very different ports. HDMI ARC (Audio Return Channel) lets your TV send sound back down the same cable to your soundbar, and when it was introduced, it combined the functions of two separate audio leads. Its audio lane, however, amounts to a narrow 1Mbps, which, despite being sufficient for stereo, compressed 5.1, and Dolby Digital Plus, is nowhere near enough for TrueHD or uncompressed multichannel sound.

HDMI eARC (Enhanced Audio Return Channel), meanwhile, boosts that to around 37Mbps, enough for eight channels of uncompressed, studio-grade PCM audio, making automatic lip-sync correction a must-have rather than optional.

The premium audio brand Sonos is upfront about it: most Atmos plays over ARC via Dolby Digital Plus, but lossless Atmos needs eARC. “Most” doesn’t mean all, however, and Apple’s support page warns users that Apple TV 4K actually uses a higher-bandwidth form of Atmos that won’t work over ARC at all. So, without eARC, an Apple TV plugged into your TV simply can’t send Atmos to your soundbar.

It’s your TV that has the final say

And it doesn’t always check in with the soundbar first

Even if you have eARC at both ends, your TV is still stuck in the middle of the conversation, and it can only pass along formats that it’s been designed to support.

DTS may be the most obvious casualty of TVs being the middlemen, as LG dropped the format from its 2025 TVs and hasn’t brought it back. That means you can route a DTS:X Blu-ray through one of these LG TVs, and your soundbar just won’t be able to get it, no matter how fancy and expensive it is.

Most TVs have a useful setting that’s kind of buried, though. In the advanced sound menu (or your model’s equivalent), you’ll probably find a digital audio output option with a mix of Auto, PCM, Pass-Through, and specific Dolby formats. Samsung has a good explainer on what these mean, but in short: Auto puts out audio in whatever format the connected device supports, Pass-Through sends the data with no processing at all (and only kicks in for external devices like a streaming box), and PCM, on Samsung’s sets at least, means left and right channels only.

PCM is tricky because it’s usually turned on while troubleshooting another issue entirely. Then it gets left on and flattens every Atmos mix into two channels, making your soundbar’s output sound oddly narrow. Switching to Auto is generally the right choice for your TV’s built-in streaming apps, while you’ll want Pass-Through for anything plugged in, such as a Blu-ray player, console, or streaming stick.

If your soundbar has its own HDMI input, you can cut the TV out of the audio path entirely by plugging your source into the speaker and using home theater passthrough to pass the picture along.

Some of it is actually the soundbar’s fault

Especially if you’re a big physical media fan

I don’t want to let soundbars off the hook entirely, because the Atmos logo says nothing about DTS, and even expensive soundbars can be selective about what they let through. Sonos’s Arc Ultra, for example, lists DTS Digital Surround among its supported formats but not DTS-HD Master Audio or DTS:X, so your Blu-ray player will have to convert these to multichannel PCM before your speaker can do anything with them.

These restrictions, even on premium soundbars, may tempt you to go cheap, but I assure you budget bars tend to be even thinner still, and we cover the pitfalls in our guide to help you avoid getting ripped off by a cheap soundbar.

If you’re a person with a big Blu-ray collection, and so DTS matters to you, I’d consider the soundbar’s decoder list against its driver count before pulling the trigger, or at least think hard about whether a soundbar or a surround sound system would suit you better (most mid-range AV receivers decode the full DTS family).

What to check before you buy

Start with what you regularly watch

If you’re primarily a streamer, eARC is very much a nice-to-have rather than an essential, with the Apple TV 4K the notable exception. If you own a DVD or Blu-ray player, or you’re planning to, the list gets a bit longer:

• eARC on both ends: Check the spec sheets for the TV and the soundbar, then check the TV’s settings, since some sets (Samsung’s among them) have a separate eARC mode that needs to be turned on.
• The decoder list, not the logo: Look for Dolby TrueHD, DTS-HD Master Audio, DTS:X, and multichannel PCM by name if discs are part of your viewing habits.
• The TV’s passthrough formats: DTS is the one most likely to be missing, so don’t assume a new TV will carry it just because your old one did.
• An HDMI input on the soundbar: It’s your route around a stubborn TV, as long as it passes 4K HDR and Dolby Vision video intact.

Getting this right the first time has never been more important, as the memory shortage is seriously squeezing home theater hardware right now, and a replacement soundbar costs more than it would have a couple of years ago.

And if you end up with a soundbar that decodes everything you need and still sounds a bit thin, the format probably isn’t the problem anymore, in which case, adding a subwoofer to your soundbar will likely do more for movie night than any single setting, and leave your TV’s built-in speakers even further behind.