Sonos Sub Speaker Review

The Sonos Sub sounds great, offering plenty of bass, and if you are happy to turn the levels up, tooth-rattling amounts of noise. It isn’t for everyone, nor will it be necessary for everyone, but the Sonos Sub is a device that is all about sound and it’s an excellent addition to the Sonos system if you can afford it. Keep reading on for the Sonos Sub speaker review.

Sonos Sub Speaker Review

Sonos Sub Speaker Review: Design

Sonos Sub Speaker Review: Design

Available in glossy black or white models, the 15.3-by-15.8-by-6.2-inch Sub has an interesting shape with a little window (the “acoustic slot”) through the middle of its body. It almost resembles a blocky, display font version of the letter O. The size is similar to plenty of subs we see, but the look is more design piece than eyesore, making its PC tower-like footprint a little easier to accept.

There are very few markings of any kind on the speaker. The front panel has the Sonos logo, and the left panel houses a status light and Join button for joining a wireless network.

Internally, the Sub employs two class-D amplifiers that power dual force-canceling drivers, positioned face to face. The Sub can dip down to 25Hz, and its highest crossover frequency is 110Hz.

You’ll want to make sure that at least one face of the Sub isn’t too close to a wall or otherwise obstructed—the ported acoustic slot needs to breathe in order for efficient driver performance. The speaker can also be placed horizontally on the floor—you’ll need to apply the felt feet for this to be feasible, but be warned that the adhesive is strong and the feet cannot be removed once placed.

The Sub sits on four feet to help minimize vibrations from transferring to the floor, but your results will vary with the type of flooring you set the speaker on. The feet also create a recessed area underneath the speaker that houses the only two connections, for the power cable and an Ethernet port. Other than the power cable, a cleaning shammy, and the aforementioned felt feet, there are no accessories. An Ethernet cable for the Ethernet port would have been nice, considering the price, but Ethernet is optional. The Sub uses Wi-Fi, not Bluetooth, so if you don’t use Ethernet you’ll need a 802.11b/g 2.4GHz router.

Performance and sound

  • Two Class-D digital amplifiers
  • Two force-cancelling speaker drivers (face-to-face)
  • Dual acoustic ports
  • Frequency response down to 25Hz

Sonos Sub - Review 2021 - Performance and sound

The Sonos Sub works with any Sonos speaker or amplified component, so while it is an excellent addition to the home cinema devices, making the already great Playbar, Playbase and Beam even better, it also adds deeper bass to any of the Sonos speakers on their own too.

The Sub works to increase the volume accordingly in harmony and – using the Sonos controller app – you can manage EQ levels at the press of a button as well as loudness. It’s very easy to use, as Sonos fans would expect.

It’s also possible to disable the Sub through “Room Settings” within the Sonos app. You’ll need to head into “Advanced Audio” and “Sub Settings” once you’ve selected the room your Sub is in, after which you can toggle the Sub on or off and change the levels – read our Sonos tips and tricks for more help here.

This will no doubt be invaluable for demoing the Sub and proving to Mrs Pocket-lint that the investment has been worthwhile. “Look you really can hear the difference,” you’ll be heard saying, and you genuinely can.

The Sub adds plenty of depth to your music regardless of the speakers you are using it with and it doesn’t rattle or vibrate either unlike some sub-woofers. This is said to be down to the face-to-face positioning of the speaker drivers.

Our first test system consisted of two Play:3 units connected in stereo with the Sonos Sub sitting in the middle of the room. We’ve also used the Sub with a Sonos Connect:Amp and two small compact speakers in a large living room and we’ve paired the Sub up with the Playbar, Playbase and Beam on separate occasions, all times with and without two Sonos One units as a stereo pair. In all instances the Sub impressed.


The Sonos Sub sounds great, offering plenty of bass, and if you are happy to turn the levels up, tooth-rattling amounts of noise.

The big concern will be that your neighbours aren’t going to enjoy your newfound love for sound, and it’s something we would definitely suggest you should consider if you’re not in a detached house in the middle of nowhere.

The Sonos Sub isn’t for everyone, nor will it be necessary for everyone, but it is a device that is all about sound and it’s an excellent addition to the Sonos system if you can afford it. For those intrigued enough to pay double what you would a regular sub-woofer, you won’t be disappointed.