Sonos’s sub mini is a powerful speaker that really packs a punch – there’s nothing small about it

Sound

For such a small box, the sub mini can make a lot of thunder. It is a fantastically booming subwoofer, which thrives even at high volumes, with absolutely zero of the buzz or struggle that can accompany some cheaper subwoofers.

Adding it to any Sonos speaker setup – which is done easily, through the dedicated Sonos app – instantly improves the sound. It adds richness and depth, and enables the traditional speakers to sing more freely.

The strength of the speaker is never too much, either, with Sonos taking a relatively conservative approach to how much bass it will actually add. Though you can turn it up (or down) in the app, the default settings (as they come from Sonos) mean you’ll get that extra thud without it turning into a muddy mess.

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The subwoofer really comes to life when it is used alongside films, to add that juddering clunk, rounded roar and unnerving rumble that can really only come from bass. Even Sonos’s smaller soundbars have decent bass performance, but the sub mini sets them free – watching various big, noisy productions, from The Rings of Power to Hereditary, was a vastly elevated experience, with the sub mini doing fantastic work in creating a base of bass that the soundbars could then build on top of.

Sonos points out that the sub mini can be used with any of the brand’s other speakers, even including its smallest ones. In practice, this is true but a little pointless – you can tell the subwoofer is overpowered for such a small speaker, and the low end is so much richer than the bass that it feels lopsided, like someone wearing huge shoes.

There might be situations where such a setup will work – if you want to buy a sub mini for the living room, but move it into the kitchen when you have a party, for instance – but generally, it is a much better decision to buy the richer-sounding Sonos five. It’s not surprising that a £199 speaker will be drowned out by a £429 subwoofer, and it is probably obvious they are not meant to sit alongside each other. But it does show that the sub mini makes more sense as part of a TV setup that is also used to listen to music, rather than a smart speaker in the kitchen, for instance.

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Sonos says the big sub is still useful to have in the line-up for bigger rooms and bigger setups. The limits of testing in a small London flat meant it was hard to see how the sub mini might fare in bigger rooms, but it seemed able to handle the biggest rooms that we could throw at it. It also coped perfectly well when paired with the Sonos arc, the biggest and most expensive part of the brand’s home cinema line-up.

So, the sub might still be valuable in a room that is taking the phrase “home cinema” very literally, for when you want to recreate the thunderous boom of the IMAX. (You can even pair two subs together, if you really want to test out the structural integrity of your house). But for everyone else, the sub mini is more than capable.

Design

Good sound is all very well, but the sub mini wants to take up space in the intimate parts of your house – it’s no good sounding nice if it looks terrible. Thankfully, it does look good – if a little strange.

Sonos has always done a fantastic job of making its speakers appear like furniture, so you appreciate their presence even when they are turned off. With a soft and friendly design language, a choice of understated colours and thoughtful sizes, they don’t stand out but are noticeable.

The sub mini carries over much of that. But it is also round – it is the size and shape of a small pedal bin, and looks enough like one that you could easily mistake it for such. It also looks a little like a small coffee table, and Sonos says you can use it as one, if you wish.

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The round shape is not only an unusual look, but means the sub mini is likely to take up more than its fair share of space. You can’t easily slot it into the corner, for instance, because it won’t sit flush with the wall (in practice, that might be a good thing, since it enables the speaker to breathe, but it is worth thinking about).

The small size does, however, mean it won’t take up much space inside any room. It also means you can, in theory, move it around – setting it up in the initial room is a dream, and it only takes a couple of taps in the app to change it to a new one. It’s not small enough that you would want to take it everywhere with you, but it’s more than fine for moving into a room for a party, for example.

Whether you like the look of the sub mini is a matter of taste. But while it does look like a bin, it doesn’t look rubbish. Once you’re used to the shape, it looks quite friendly and the roundness becomes charming rather than alarming.