Michael Gowan/CNN

If you wanted lots of bass with your Sonos sound system, you previously had two limited choices: Take what the soundbar or speaker delivered on its own, or add the huge — and hugely expensive — Sonos Sub. Now we have a reasonably sized (and priced) alternative in the $429 Sonos Sub Mini.

The slick-looking wireless subwoofer is an excellent complement to your existing Sonos system, though it’s not essential. But if you find that you miss a tactile rumble while watching stuff blow up in action movies or feeling the low end of music in your bones, the Sub Mini should satisfy your craving.

A good, affordable subwoofer for Sonos users
The Sonos Sub Mini is a wireless subwoofer that you can add to your Sonos system. It brings an extra dimension to your listening experience, both when watching TV and movies or listening to music. While it is more affordable than Sonos’ other subwoofer, it still costs a lot.

What we liked about it

It brings more bass to your Sonos sound

Michael Gowan/CNN

Sonos speakers have pretty impressive bass on their own; that’s one of the reasons that we often recommend its soundbars and speakers. But there’s usually that caveat of “good bass without a subwoofer,” which is not the same as great bass.

The Sonos Sub certainly brings the boom, but at $749, only people without a budget and plenty of space could add it to their system.

With the more affordable Sub Mini, more people can experience what a Sonos system sounds like with a subwoofer, and I can say unequivocally that the Sub Mini improves the sound of every Sonos speaker you pair it with.

It works with most Sonos speakers

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It was fun to play “Which speaker gains the most from adding the Sub Mini?” A subwoofer is a natural pairing with a soundbar, such as the Beam. But you can also connect it to most other Sonos speakers. The exceptions are the two portable models, the Move and the Roam.

Among the soundbars, the Beam benefited the most. While the Beam has good bass for a small soundbar, I wouldn’t go so far as to say it delivers enough bass. The Sub Mini solved that. When Mount Doom erupts in “The Lord of the Rings: The Rings of Power,” the Sub Mini provided the tactile push and rumble that was missing. The subwoofer also adds gravitas to dialogue and voices, such as during Peter Coyote’s narration in Ken Burns’ “The U.S. and the Holocaust” as well as less weighty discussions, such as Joe Buck and Troy Aikman’s commentary during Monday Night Football.

Sonos’ premium soundbar, the Arc, produces better bass itself, so while the Sub Mini improved on the low end, it was not as noticeable. The Sub Mini certainly boosted the bass when paired with the budget-minded Ray, but adding a $429 subwoofer to a $279 soundbar doesn’t make much sense; spend the money on upgrading to a Beam instead.

A surprise was how good music sounded when adding the Sub Mini to two Sonos One speakers. A pair of Ones set up as left-right stereo speakers already have an impressively wide sound; the Sub Mini adds more depth to the vocals and instruments, and the thumping drum track on Drake and 21 Savage’s “On BS” radiated throughout the room.

It’s easy to set up

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As with all Sonos speakers, setting up the Sub Mini is a breeze, especially because you’ll be adding it to an existing system. After I plugged in the Sub Mini, the app recognized it quickly and walked me through the rest.

To add the Sub Mini to another speaker, go to Settings, then select System and pick a room or speaker to pair it with. It’s also easy to change which speaker it is paired with (though it can only be paired with one room or speaker at a time).

There is just one button on the Sub Mini, which can reconnect it to your Sonos system. Everything else is done through the app, though there’s not much to adjust. You can increase the bass level or change the phase (which adds delay to the signal and in some rooms can improve the low-end effect). Remember to run TruePlay after you’ve connected the subwoofer to get the best sound for the space you’re in.

What we didn’t like about it

It’s still expensive

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While it’s cheaper than the $749 Sonos Sub, the Sub Mini is still pretty pricey at $429. Unfortunately, you don’t have other options if you want more bass for your Sonos system.

You may want to spend those dollars elsewhere. For example, if you have a Beam or Arc, you might want to add two Sonos Ones as surround speakers — the encompassing effects could improve your experience more than the subwoofer.

But if you’ve already got a full surround sound setup or really just crave more bass, the Sub Mini will be a welcome addition to your Sonos family.

It’s not that ‘mini’

Despite its name, the Sub Mini isn’t that small. Sure, it’s smaller than the 15.8-inch-by-15.3-inch-by-6.2-inch Sonos Sub, but, in reality, the 12-inch-by-9.1-inch Sub Mini is about the same size as most wireless subwoofers that come with a soundbar.

However, it does look better than most subwoofers. The cylindrical unit features a “tunnel” in the side that looks cool, but also has a function — instead of having a woofer firing down or out, the Sub Mini has two 6-inch woofers that face inward, pointing at each other. Sonos says this design maximizes the bass output.

Bottom line

The Sonos Sub Mini isn’t a necessary part of your Sonos system, but it will make it better. Sometimes, like when you’re watching things explode, the effect is dramatic. At other times, like when you’re listening to dialogue, it’s subtler. But you’ll always hear an improvement.

Whether that improvement is worth $429 depends on how much you like bass — and how invested you are in your Sonos system. It’s worth mentioning that the Sub Mini only works with Sonos speakers. But if you’ve got another type of soundbar or speaker, you have options. For example, the $180 Roku Wireless Bass Pro matches with a Streambar Pro, and Polk’s $170 React Sub goes with its React soundbar. Both cost much less, but the low end they provide is less detailed.

For me, the Sub Mini was the add-on I’ve been waiting for — that extra oomph may be what finally allows me to replace my home theater system.