One of the best soundbars I've tested this year is refreshingly compact (and cheaper than rivals)

ZDNET's key takeaways

The new Bose Smart Soundbar is available for $499 This soundbar offers premium features like AirPlay, Dolby Atmos, and unique integration with Bose earbuds Its standout software features can be hit-or-miss.

These days, a soundbar is a vital component of your home TV setup. If your TV speakers aren't doing the job, but investing in a sound system is too much of an expense or commitment, you're probably in the market for a soundbar. 

Although soundbars are an alternative for budget-conscious home theater fanatics, a potential buyer might assume that the bigger the soundbar, the better the audio experience. But that's not always the case, and Bose proves it. Bose's latest Smart Soundbar debuts with a compact form factor, plenty of high-quality audio features, and one feature exclusive to the Bose Ultra Open earbuds, which I'll touch on later.

Also: One of the most immersive soundbars I've tested isn't made by Klipsch or Bose (and it's $200 off)

The new Smart Soundbar is a refreshed version of the Bose Smart Soundbar 600. It has the same dimensions, connectivity, and speakers as the 600. Two software features distinguish the new Smart Soundbar from the older Smart Soundbar 600.

The first software feature, AI Dialogue Mode, uses machine learning to adjust your audio's tonal balance. As a result, the soundbar will enhance or minimize lower- or higher-frequency sounds in real-time to help you hear dialogue more clearly. 

AI dialogue didn't compromise the loudness or intensity of explosions or musical stings while I watched Twisters. And while the loud winds of the tornadoes in the movie ripped through the town, I could still hear what Glen Powell was saying through his character's thick country accent.

Also: Bose Ultra Open review

During Monday Night Football broadcasts, the AI dialogue feature made the broadcasters' voices sound strange, forced, and unnatural unless the fans in the stadium were drowning out their voices. This feature is useful, but only when you're having genuine trouble hearing the speakers' voices.

Historically, soundbar software features were reserved for the TV you connected to it, but companies are looking for new ways to engage users' headphones in their home audio experience beyond simply connecting the two via Bluetooth.

Earlier this year, Sonos released the Sonos Ace headphones, which debuted with a feature called TV Audio Swap. This feature is compatible with select Sonos soundbars and swaps audio from the soundbar to the headphones to supply the wearer with a private, immersive watching experience.

Also: Sonos just brought TV Audio Swap to more devices. Here's why it's my all-time favorite headphone feature

Bose responded with a similar idea, integrating the Bose Ultra Open headphones into the new Smart Soundbar's user experience. The Ultra Open are open-ear earbuds that provide users with an unobstructed listening experience, so their integration with the soundbar is unique.

Bose's new Personal Surround Sound feature engages the Ultra Open to act as rear surround speakers when using the Smart Soundbar. You can toggle this feature in the Bose app, and I used it when streaming Can't Get Enough by J. Cole on the soundbar via AirPlay. 

Unlike Sonos' TV Audio Swap, Bose's Personal Surround Sound doesn't mute the soundbar once the earbuds enter the chat. You can still hear the soundbar clearly, thanks to the earbuds' open design, and the earbuds supply a subtle boost to the soundbar's audio output. And it is very subtle.

Otherwise, the new Smart Soundbar is equipped with AirPlay, Bluetooth, Spotify Connect, and built-in Chromecast and Roku TV. Amazon's Alexa and Google's voice assistant are compatible with the soundbar, and Dolby Atmos is available. 

Also: What is spatial audio? Here's everything you need to know

If your TV doesn't have an eARC port, which encodes audio in Dolby Atmos, Bose's new soundbar is fitted with Bose TrueSpace processing. This feature processes non-Atmos audio and adds more height and depth to the audio through the upfiring speakers, heightening the immersive experience. You can plug the included optical audio cord into your TV and download the Bose app to tweak the height of the audio channels.

ZDNET's buying advice

The new Bose Smart Soundbar is a great way to upgrade your home audio setup compactly and more affordably. Bose's latest soundbar offers some of the same audio features found in the Sonos Arc and Sennheiser Ambeo soundbars for at least $400 less. 

If you have a small space or want a new, high-quality soundbar for a lower price, Bose has you covered. The Smart Soundbar is smaller than you'd think, and its sleek and unassuming design blends into any home decor aesthetic.

That said, you don't need to purchase the Ultra Open earbuds to get the most out of this soundbar. The Personal Surround Sound feature is cool if you already have the Ultra Open and are considering this soundbar. However, the feature adds so little to the overall user and listening experience that it's not worth spending an extra $300 for the earbuds. For $100 extra, you can buy a pair of Bose surround speakers.