Sonos Sub 4 reviewed: big bass

If you’re living in the Sonos ecosystem and need a bit of bass, the Sub 4 could be right up your alley. But if you have an older Sub model, it might not make a big difference.

Soundbars may well come with a smattering of bass, but there’s always room for a little bit more. Much like how there’s always room for a little pud, there’s always room for a little more bass, as well, provided you have the hardware to make it happen.

In the Sonos ecosystem, that’s through a Sonos-made subwoofer and nothing else, because you need Sonos gear to inside that world. Short of the few Sonos speakers made by IKEA, little else fits into a Sonos speaker set, and if you want more bass, that means a Sonos sub.

We’ve seen a few of those over the years, notably including the mini model that was a bucket of bass in the aptly named Sub Mini. But what if you fancy that little bit more, and you have a soundbar to match?

For that, you’ll want to check out the latest model, the Sub 4. That is provided you don’t have the Sub Gen 3 before it.

What is the Sonos Sub 4?

Sonos already equips its soundbars and speakers with a reasonable amount of heft and bass, and the most recent Arc Ultra has what is clearly the next generation of that technology in Sound Motion. A small box capable of generating larger amounts of air and in turn bigger bass, it could well be enough bass for small living rooms.

But if you need more, the Sonos Sub series has long been for you.

The Sub Mini was the most recent attempt, delivering a bucket of bass in the easiest way possible without breaking the bank. The result was ostensibly a bucket of bass, which was really what it looked like.

While the Sonos Sub range has often been a stylised minimalist subwoofer in a square of sorts, the Sub Mini was basically a bucket that managed to pack in a surprisingly loud subwoofer of sorts.

The latest Sub, the Gen 4 also simply called the Sub 4, is more like the standard stylised subwoofer Sonos normally makes, complete with most of that same minimalistic design.

It includes two Class-D amps made to manage to two woofers arranged inward to cancel force and distortion, including WiFi 6 to connect to wireless networks and a 10/100 wired Ethernet port if you prefer to hard-wire your sub.

What does it do?

Beyond the paint job, you probably won’t notice a lot of difference between the Sub Gen 3 and the Sub 4, though the new model has lost the name “gen”. It is the fourth generation Sonos Sub, sure, they’ve just cut the name a bit.

But Sonos has also made a change to the construction, because the new model is lighter. You’ll feel it when you pick the Sub 4 up, particularly if you had the original. There’s nearly a good two kilograms difference, and you can feel the difference, with the Sub 4 weighing 11.79 kilos and the Sub Gen 3 at just over 13.

Hopefully you won’t have to move it very often, and can just leave it in the one place, because that’s what a subwoofer is meant for.

Sit the Sub 4 upright or lie it down — both are supported — and then hook it up to your Sonos system to flesh out the lows of the bass. This isn’t a speaker in its own right, and needs other Sonos speakers to do its job, providing earthy lows to the Sonos Arc and Arc Ultra, Sonos Beam, as well as Era 300, Era 100, and other Sonos speakers. It’s that extra bit of bass you might want in your soul.

Does it do the job?

Plug and play just about covers how the Sub 4 works: take it out, plug it in, and connect it up with a Sonos system. It is as easy and as seamless as subwoofers get.

You’ll want to use the Sonos technology of TruePlay to tweak and match the subwoofer to your surroundings, though, as the system works out the sub signal to match your speaker system.

From there, you can start getting stuck into music and films.

We spent our time with two playlists, the Pickr Sound Test and the extended Pickr Bass Sound Test, which we bring out for speakers that emphasise the lows. And it shows, particularly with the intent of nailing the lack of distortion, something Sonos talks up thanks to the force cancellation of the two subwoofers in this unit.

Testing with electronic focused entirely on the subwoofer with a few different tries, we find the big drop of bass in Tycho’s “Glider” really kicks in when the sub is set to bass at plus three, while that same drop is staggeringly hard at eleven. Yes, we turned it up to eleven just like in Spinal Tap, but that’s not even the loudest setting.

The Sub 4 supports positive 15, which seems like an arbitrary way to say “so much bass, you won’t know what to do with it”. At plus 15, the Sonos Sub 4 feels like it’s going to move the foundations of the room, so after a little reverberation in Tycho and Daft Punk, we turn it down. We’ll be back later, don’t you worry.

For now, we use it across the spectrum of music in our sound tests, and our results show that plus two feels underpowered, while plus four is very much a Goldilocks “just right”. It’s that sweet spot, delivering just the right amount on Ariana Grande’s “Into You” and Mark Ronson’s “Uptown Funk”. It’s even the right amount for the guttural bass to make a dent in FKA Twigs’ “Two Weeks”, complete with zero distortion. Absolutely none. The signal is cleaner than just about anything else out there.

It’s the same experience regardless of what music style we subject to the Sub 4, be it the heft of lows in the hard rock of the Deftones or the light punchy rounded bass from Paul Simon.

In jazz, you’ll find really well rounded lows that just help the sound to be that much clearer. From our Miles Davis test track in the main sound test to the Charles Mingus in our bass playlist, the sound is spectacularly punchy and clear in the lows, which is just where it needs to be.

We even ran it with our soundbar test, playing the Sub for films, which is clearly going to be a main use. Unsurprisingly, the lows felt stronger all around: a bigger impact in the thumps and explosions in Mad Max, in Edge of Tomorrow, and the gun shots in John Wick, too.

So we decide to return and turn that bass up again.

We wanted to see just how far you needed to flex the Sub 4 to get some distortion. It turns out, you really need to hit it with the bassiest tracks to get some fuzz.

Billie Eilish’s “Bad Guy” turns out to be just that track, punchy at the sweet spot of plus four, but boom-boom-shake-the-room staggeringly loud at the maximum of fifteen.

Turn the Sonos Sub 4 up to its maximum and the heaviest of bassy tracks will hear some distortion, though it’s not much at all. The final 30 seconds where the bass really kicks in were heavy, something that wasn’t a surprise, and about the only time we picked up on a modicum of distortion. Everything else about the song was largely distortion free.

It’s impressive, to say the least.

What does it need?

And virtually nothing is wrong with the Sub 4. If anything, Sonos has improved upon the formula by making the whole thing that little bit lighter.

There’s just one issue: it’s not dramatically different from the Sub Gen 3. Not at all.

If you have the Sub Gen 3 already, you basically have the Sub 4, albeit with a little more in the weight. However, subwoofers aren’t one of those products you regularly move, so this isn’t really an issue. Once you put a subwoofer down in place, that’s it; you’re not moving it again for a while, probably until you move.

So there’s no reason for a Sub Gen 3 owner to upgrade to a Sub 4 at all. If anything, the only reason you might consider buying one of the new subwoofers is the Gen 3 can be paired with a Sub 4 for extra bass, but weirdly, there’s a catch on that, as well.

While both the third- and fourth-generation Sonos Sub models can be paired together, neither supports a dot two subwoofer configuration where they handle two elements of bass for a room. That is to say a 7.1.2 system where you have seven surround channels, one bass channel, and two height channels can’t currently be upgraded to support 7.2.2 with two bass channels. It’ll just boost the one bass channel to be bigger bass without handling two sub channels.

Even though subwoofer channels max out at two, and high-end amplifiers can technically handle two sub channels for seven, nine, and 13 channel surround systems, the Sonos maxes out at one subwoofer channel even if two subs are plugged in. You’ll get more bass with two units, sure, but until Sonos supports two subwoofers operating as two channels, it won’t function like a two channels subwoofer system.

Is it worth your money?

At $1299 in Australia, the Sub 4 is pricey, particularly given how Sonos sound systems already have a decent smattering of bass inside. Depending on how much you love the lows, you may not even need a subwoofer for your Sonos sound system.

But even if you do, Sonos has a mid-range subwoofer in the $699 Sub Mini, and that could be more than enough for your needs. Meanwhile, the newer Sub 4 technically has a little more going for it, and really plays well to two types of buyer:

• Someone who wants the best of the best, and
• Someone with a large and spacious living room.

Both are great subwoofers, but the Sub 4 is just that little bit better, hardly surprising given the bigger price tag. It’s also larger in general, so it has more to work with where it counts. For folks who need that, it’ll make a difference for sure.

Alternatively, the existing Sub Gen 3 could also be found around the tracks, either sold for less at retailers with older stock or pre-owned. If you need the Sub 4 at a slightly lower price, the Gen 3 may be an option, provided you can still find it.

Yay or nay?

We’re writing this review on the basis that you probably won’t be able to find the Sub 3 for very long, and a glance around the web suggests that to be true. The Sub 4 is here to stay, while the Gen 3 will disappear, as most older products eventually do.

For people who need a lot of bass in a big room to go with their Arc, Arc Ultra, or Beam purchase, the Sub 4 makes sense, but we’d caution the roughly double the Sub Mini spend if you don’t actually need it.

There’s a lot of bass here, for sure, but the price may not justify the means of getting there, especially when a slightly older model or smaller Sub Mini might get you a solid result for less.