Sony SRS-XB33 review

This diminutive dynamo speaker from Sony will get the party started – any time, anywhere

Sony SRS-XB33 review
(Image: © Sony)

Louder Verdict

It may be tiny but the Sony SRS-XB33 is packed with features, not to mention a surprising amount of power. With excellent battery life and a durable build, it's a great-value choice for portable partying.


  • +

    Surprisingly loud for its size

  • +

    Tough as nails

  • +

    Great lighting system


  • -

    EXTRA BASS mode can be too much

  • -

    Accuracy wanes at high volumes

  • -

    Treble is a little stifled

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According to its official marketing spiel, the Sony SRS-XB33 ($150/£150) will enable you to “party wherever, whenever”. While that claim shouldn't be taken literally – after all, no one wants to hear Paradise City blasted out in the middle of a funeral – it's clear the Japanese manufacturer was focused on portability when it made this speaker. 

With its compact size, generous battery life and ability to withstand outdoor use, it ticks a lot of boxes for music lovers on the move. And that's before you even get on to fancy features like Extra Bass, Live Sound and a multi-coloured light show.  

In this Sony SRS-XB33 review, we'll take a closer look at the aforementioned attributes, give our opinion on the speaker's sound and, ultimately, let you know whether the Sony SRS-XB33 deserves a place in your house, garden or wherever else you wish to get on down.

Sony SRS-XB33 speaker review: Design

Unlike the other products in our loudest Bluetooth speakers guide, the Sony SRS-XB33 is a diminutive device, measuring just 9.8 x 3.8 x 4.1 inches (246 x 97 x 106mm) and weighing a mere 2.4lbs (1.1kg). That makes it easy to lug around on your travels – indeed, so light is the speaker that it doesn't even come with a carry handle. If you wish to use the SRS-XB33 at home, its size makes it suitable for perching on a bookshelf or kitchen work surface (it works standing up or lying down); and with black, blue, taupe and red versions available, you can choose one that matches your home décor.   

The control panel is situated at the top of the speaker, a thin island of rubber in a sea of cloth mesh. There, you'll find buttons for switching the unit on, pairing your device, playing/pausing your music and making/taking calls, turning the volume up and down, and switching between Live Sound, Extra Bass and Stamina modes. 

Skipping forward a track requires you to press the play/pause/call button twice, while skipping backwards means having to hit that button three times. It's a bit fiddly, to be honest, so you might find yourself using the Sony Music Centre app to control your music – more about that in the next section. Another thing we found with the control panel on the speaker was that it was hard to see in low light. The embossed design helps you to feel your way around, but some illumination would've been nice.

At the back, there's another small panel featuring a USB-C port for charging the device, a standard USB one for replenishing your smartphone or tablet while you listen to music, along with buttons for checking how much battery you have left, activating Party Connect mode (where you can pair the speaker with up to 100 compatible wireless devices) and launching Stereo Pair (which enables you to hook up a solitary speaker for a more spatial listen).   

As for the shape of the Sony SRS-XB33, it's slightly off-centre. While this might irritate those who crave symmetry, Sony claims that the optimised weight balance helps to enhance clarity and widen the soundstage. Inside the speaker, the manufacturer has installed its newly developed X-Balanced Speaker Unit, a non-circular diaphragm that's designed to deliver punchier bass while reducing distortion. 

To further enhance the bottom, Sony has built the speaker with passive radiators on either side. How much difference all of this makes to the overall listening experience, we'll explore in the 'Sound' section further down the page.

Sony SRS-XB33 speaker review: Features

Sony SRS-XB33

(Image credit: Sony)

Think a speaker this small couldn't possibly have a lot of features? Then you'd be wrong! Pairing with your device via Bluetooth 5.0, NFC or  SRS-XB33 actually has a few tricks up its sleeve, some of which are branded in capital letters to highlight just how cool they are. The first of these is Live Sound, an optional feature that relies on digital signal processor (DSP) technology to present a three-dimensional soundstage that's meant to recreate a festival experience. 

Considering the sound quality at outdoor gigs tends to be rather wishy-washy, we're not sure why anyone would want this – we found the feature to be a bit pointless. As the name suggests, Extra Bass gives the low frequencies a boost, while Stamina mode will limit the amount of volume you can get out of the speaker, enabling you to preserve battery life. There's also a feature called ClearAudio+, which sees the speaker adapting its soundstage to suit the kind of music you're playing.  

Speaking of battery life, it's very good. With Extra Bass activated and the lighting system in full swing, you'll get up to 14 hours of listening, but that jumps to 24 hours with those features switched off. 

The lights are actually pretty awesome considering the size of this device, with both the vertical lines at either end of the speaker and two 'eyes' inside the speaker flashing in different colours in time with the music. Note that you can customise this using either the Sony Music Center or Fiestable app. The former also allows you to adjust the equaliser settings, switch between Bluetooth and audio-in modes, group the speaker with other similar devices and more.   

Last but certainly not least, this speaker is 'proofed' to within an inch of its life. IP67 rated, it'll survive being dropped, covered in dust and even dunked in salt water – which you'll be thankful for if you ever fall asleep while the tide's coming in.  

Sony SRS-XB33 speaker review: Sound

Obviously, a speaker of this size and power (2 x 8W) isn't going to fill a field or even a very large garden with sound. However, the SRS-XB33 still produces a surprising amount of volume. Turn it up to the max and you'll struggle to strike up a decent conversation if you're standing next to it. 

The bass is also a revelation, those dual passive radiators adding real thunder to bottom-heavy bangers such as Black Sabbath's Paranoid and Cream's Sunshine Of Your Love. Actually, we felt that the Extra Bass mode could be a little over-bearing on such tracks, but you might find it more useful when listening to ballads. 

The SRS-XB33 strikes a nice balance in the mid-range, delivering vocals and keyboard lines with just the right amount of richness. However, the treble was a little stifled for our liking, meaning we had to make a few tweaks using the Sony Music Center app to bring out those hi-hats. We also found that the speaker lost some of its accuracy at the highest volumes – though no one is likely to care too much about that once the party is in full swing.

Sony SRS-XB33 speaker review: The alternatives

If you're looking for a go-anywhere speaker but don't have the budget for the Sony SRS-XB33, then the JBL Clip 3 ($67£49) is a very decent alternative. Pairing with your device via Bluetooth or 3.5mm mini-jack, this teeny tune box comes with a carabiner that enables you to hang it from your bag or belt while you walk along. It’s surprisingly rugged, too, its IPX7 waterproof rating making it the ideal choice for festival goers.     

Need something with a bit more oomph? Offering a massive 126dB of volume, the Anker Soundcore Rave ($220/£199) is one of the loudest Bluetooth speaker you can buy right now – and it just so happens to sound great, too. Yes, it's a hefty lump but, thanks to its built-in carry handle, you can easily lug it from one party to another.

Paul Dimery

Paul has spent the past eight years testing and writing about gadgets and technology for the likes of Louder, T3 and TechRadar. He might not have the wealth or the looks of Tony Stark, but when it comes to knowing about the latest cool kit, Paul would surely give Iron-Man a run for his money. As for his musical leanings, Paul likes everything from Weyes Blood to Nirvana. If it's got a good melody, he's on board with it.