Sonos has just revealed the brand new Sonos Beam, a smart home theater soundbar with Amazon Alexa that might possibly be the best accessory to the Amazon Fire TV that you could buy. At its core, the Beam is a premium soundbar that costs $399, which, while not cheap, is $300 less expensive than Sonos’ other soundbars, the Sonos Playbase and Playbar. It’s also a smart speaker with hands-free Alexa built-in and will eventually support Google Assistant as well as Apple AirPlay 2. Unlike most soundbars, which usually connect via optical audio, the Sonos Beam connects via a single HDMI-ARC port, which is how it achieves some of its most interesting features and becomes a great companion to the Amazon Fire TV.

If you’re wondering how a soundbar could work with just a single HDMI port, you’re probably not alone. ARC, which stands for Audio Return Channel, is one of the newer parts of the HDMI spec that was added in 2009 and has been seeing rapid adoption. While everyone knows HDMI is how you get video into a TV, HDMI-ARC allows the TV to simultaneously send audio back out over the same connection.

If your TV supports HDMI-ARC, you connect the Sonos Beam to the TV’s HDMI-ARC port, which is usually HDMI 1, and connect your other devices, like a Fire TV, to your TVs other HDMI ports. When you set your TV to HDMI 2, for example, to use your Fire TV, the TV simultaneously sends all audio through the HDMI-ARC port to the Sonos Beam.

By connecting over HDMI, instead of optical audio, the Sonos Beam is able to achieve interesting things, like turn the TV on or off. Using its five far-field microphones and built-in hands-free Alexa capabilities, you can say “Alexa, turn on/off the TV.” Even better, thanks to Alexa’s ability to control the Fire TV, you can say “Alexa, play The Grand Tour” with the TV off and the TV will turn on, switch to the Fire TV’s input, and start playing your requested video without ever having to touch a remote.

Of course, this all only works if your TV supports HDMI-ARC. Sonos says they tested hundreds of TVs and that they estimate that 80% of new TVs will automatically work with the Sonos Beam, while others will need some settings tweaked. For TVs that don’t support HDMI-ARC, Sonos is including an optical audio to HDMI adapter in the box, but if you use it, you’ll expectedly be unable to control the TV with Alexa.

Interestingly, the Sonos Beam does not come with a remote. Instead, you control its volume either by voice or using your TV’s remote. If your TV supports HDMI-ARC, pressing the volume buttons on your TV will automatically change the volume on the Beam instead of the TV’s built-in speakers. For older TVs, the Beam has an IR receiver to pick up your TV remote’s signal.

The Sonos Beam has a single center tweeter and four woofers, two of which are pointed straight ahead on either side of the tweeter and two are angled out of the side of the Beam. It also has three passive radiators to move air and add warmth to the base.

Despite the sophisticated speaker arrangement, the Beam is not trying to be what it is not by simulating surround sound, like other soundbars. It is a 3 channel speaker, with only right, left, and center channels. For a 5.1 surround sound setup, you can add a pair of Sonos One speakers or Sonos Play:1s in the rear and a Sonos Sub. Even with that setup, however, you’re only looking to achieve Dolby Digital surround since the Beam does not support Dolby Atmos.

While the Sonos Beam can be used for a full surround sound setup, that doesn’t seem to be the target use case. It seems more meant for people upgrading from their TV’s speakers. In that scenario, by connecting just one HDMI cable, you’ll drastically improve your home theater experience without completely overhauling your setup. Sonos is also selling a wall mount for the Beam to achieve a minimalistic clean look.

The Sonos Beam also has a few neat tricks up its sleeve that are specific to home theater usage. It’s able to differentiate audio coming from a TV, from something like streaming music, and emphasize dialogue in the process. It also has a night mode where it will boost the volume of quiet sounds, like whispers, while lowering loud sounds, like explosions, so you that you can watch content at an enjoyable level without needing to constantly adjust the volume to keep from waking people up.

The design of the Sonos Beam is simple but modern. Along the top are volume up/down, track forward/reverse, and play/pause buttons, as well as a microphone mute button for Alexa. Along the back you’ll find that single HDMI-ARC port, 10/100 Ethernet, the power plug, and a sync button for setup. Of course, it also has WiFi, but it’s only 802.11b/g because it uses the 5GHz band to connect wirelessly to other speakers, like the rears and subwoofer in surround sound setups.

For those who want a simple soundbar with some real smarts, the Sonos Beam seems like a great option, especially for Fire TV owners, thanks to its Alexa control. However, with the Fire TV Cube likely just around the corner, it’s unclear how well the Beam’s Fire TV controls will work when two devices are able to control your TV via hands-free Alexa commands. The Sonos Beam is available to pre-order now for $399 and will launch on July 17th.