Bose SoundLink Flex review

A stylish, portable Bluetooth speaker that gets the job done Tested at £149.95 / $149 / AU$249.95

Wireless speaker: Bose SoundLink Flex
(Image: © Future)

What Hi-Fi? Verdict

There are more rugged and better-sounding options, but the Bose SoundLink Flex is an easy to use Bluetooth speaker that looks and sounds good


  • +

    Clear and detailed midrange

  • +

    Sleek, waterproof design

  • +

    Easy to use


  • -

    Rivals offer a more balanced, precise sound

  • -

    Design could be more rugged

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Sometimes you need simplicity in your life. You want a portable Bluetooth speaker that does what it says on the tin? You got it: the Bose SoundLink Flex is portable, easy to use, and plays any music through Bluetooth within seconds. Job done. 

Sure it has other features (speakerphone, party mode) and it comes with an app. Instead of getting overwhelmed with features, though, Bose just wants you to listen to music, anywhere you can carry the speaker to.


Wireless speaker: Bose SoundLink Flex

(Image credit: Bose)

You can buy the Bose SoundLink for £149.95 / $149 / AU$249.95, which places it slap bang in between two five-star JBL speakers: the Award-winning JBL Charge 5 (£160 / $180) and the newer JBL Flip 6 (£130 / $130 / AU$200). 

We expect to see some good deals down the line for this Bose speaker, which will surely be welcome to those wanting to save some pennies without sacrificing enjoyment. 


Wireless speaker: Bose SoundLink Flex

(Image credit: Future)

The Bose cuts a slim profile, and its 600g weight makes it light enough to carry with one hand or slip into a bag. The fabric loop can be attached to a carabiner or you can hook it around your finger. It’s a portable design in every sense, although we find a cylindrical design like the JBL Flip 6 – which is also 50g lighter – easier to carry and fit into small spaces.

The speaker has a soft-touch silicone exterior and a powder-coated steel grille on the front, and it’s available in four finishes: Black, White Smoke, Stone Blue and our review sample’s limited edition Carmine Red. It’s designed to be tough enough to withstand knocks and tumbles in the great outdoors, and Bose says the speaker’s finish won’t peel or flake, and is resistant to rust and UV light. 

Bose SoundLink Flex tech specs

Wireless speaker: Bose SoundLink Flex

(Image credit: Bose)

Finishes Black, White Smoke, Stone Blue, Carmine Red 

Battery life 12 hours

Waterproof rating IP67

Bluetooth version 4.2

Dimensions (hwd) 9 x 20.1 x 5.2cm

Weight 600g

You can also place the Bose speaker anywhere indoors and it won’t look out of place: we used it in the kitchen, home office and even the bath. With its IP67 rating, the SoundLink Flex is fully waterproof and dustproof, so we don’t mind getting splashes of water on it and the finish is wipeable too. It’ll even play when dunked in water – we submerged our sample underwater and it carried on playing, albeit in a muffled way. It also floats, and the speaker performs perfectly well after it’s dried out too.

The Flex looks and feels more sophisticated than the JBL and Ultimate Ears Wonderboom 2 speakers, which are very much designed to get dirty. When the soft-touch finish of the Bose picks up a lot of dirt, debris and grass from being placed in the garden, we feel like we’ve done something wrong. We quickly scrub it off, but some stains remain and we feel like we’ve tarnished it. Conversely, we have no such qualms about getting the more rugged exteriors of the JBL or UE speakers dirty or keeping them clean. But we’d think twice about taking the Bose to a music festival.

On a happier note: the speaker sounds good wherever you place it and in whichever position. This is thanks to Bose’s PositionIQ Technology, which uses built-in sensors to detect the orientation the speaker is in – lying flat on its back, standing up, propped against a wall in portrait mode – and adjusts its EQ and optimises the sound accordingly. We find this works really well – the sound comes through evenly however we place the speaker.


Wireless speaker: Bose SoundLink Flex

(Image credit: Future)

You’ll get plenty of music out of the Bose, as it has a hefty 12 hours of battery life on a single charge. You get a similar 12 hours with the JBL Flip 6 (but it takes half the time to charge up), while the JBL Charge 5 goes much longer for 20 hours. 

It takes roughly 4 hours to charge the Bose speaker up to full power using the provided USB-C charging cable.

The SoundLink Flex has Bluetooth 4.2 on board – not exactly cutting edge when similar speakers from JBL are now sporting Bluetooth 5.1. Still, pairing to a smartphone takes mere seconds and it automatically reconnects to the last device it was paired with. You can also have two devices connected to the speaker at the same time – we had an Apple iPhone and a Samsung Galaxy smartphone connected to it simultaneously. You also get a wireless range of up to a claimed 9m/30ft. 

The control buttons on the speaker – power, volume up and down, Bluetooth pairing and multi-function that pauses, plays, skips music and takes calls – are responsive and instinctive to use from the second you get it out of the box. You can also press and hold the multi-function button to activate your phone’s voice assistant. 

Download the Bose Connect app and you get a few more features, the most useful being battery life status. The LED next to the power button stays solid white when fully charged, and glows red when low. But there’s no indication of how much battery life is left on the unit, so it’s worth downloading the app just to keep tabs on that. 

Other features in the app include setting the auto-off timer, seeing the two devices you’re connected to, controlling music playback and, most importantly, turning off the rather annoying voice prompts if you don’t need it. There are no EQ sound settings to tweak yourself, however – Bose’s PositionIQ tech seems to be enough.

The Flex can be used as a speakerphone thanks to its built-in mic, and you can pair two Bose SoundLink speakers together in stereo or party mode using the app. You can also connect the Flex to other SimpleSync-compatible products, which include Bose soundbars and headphones like the Bose 700 and QuietComfort Earbuds


Wireless speaker: Bose SoundLink Flex

(Image credit: Bose)

Pairing and playing is easy: this is a straightforward Bluetooth speaker, and we love how easily we can start listening to music within seconds.

Inside the speaker is one custom-designed driver and two small passive radiators (front and rear facing) that deliver Bose’s larger-than-its-size sound. That’s the first thing we notice: the sound from this compact speaker goes big and loud.

The second thing we notice is that voices take centre stage. If you’re a podcast fan, you’ll love the Flex. Voices come through cleanly and clearly, with plenty of detail expressing tone, excitement and the nuances in each host’s voice. 

Switch to music, and Taylor Swift’s vocals on no body, no crime are beautifully delivered. The Bose does a great job of balancing the delicacy and suspicion evoked in her vocals in equal measure. 

It’s an enjoyable performance. We play Randy Newman’s greatest hits and spend a great time in his company, with the speaker relaying the jaunty melody of You’ve Got A Friend In Me and various orchestral film soundtracks with ease. 

Basslines are ample and plump, but they could be deeper and more well-defined. The rival JBL Flip 6 does a better job of delivering a taut and grippy low end, as well as sounding clearer and more balanced across the frequency range. 

We wish the Flex gave other areas as much consideration as the vocals. Drums, guitars, synth effects and voices can sound rather detached from each other in the mix. Through the JBL, piano notes sound sweeter and more textured, drums hit with crisp precision and impact, and it’s much easier to accurately place everything in the mix. The Bose speaker is a touch reticent in comparison. 

The Bose is no slouch, though: whether you’re listening to Rage Against The Machine, Dua Lipa or the Game Of Thrones soundtrack, it has more than enough punch and flow to hold your interest.

It’s only in comparison with the JBL speakers that we pick out shortcomings. Push the volume too high and the Bose starts to get a little muddled. It’s not quite as effortlessly room-filling as the JBL speakers, which also retain their composure at very high volumes. 


Wireless speaker: Bose SoundLink Flex

(Image credit: Future)

The Bose SoundLink Flex is a wonderfully easy to use, straightforward, portable Bluetooth speaker. The thing is, there are other wireless speakers around and they do it that bit better. The JBL rivals are still the ones to beat – the Flip 6 is cheaper, more rugged, and it sounds better.

Despite all that, we enjoy our time with the Bose. It’s nice to have it playing while we work or cook dinner. It might not lead the field, but it gets the job done, and we appreciate a fuss-free music experience. 


  • Sound 4
  • Features 4
  • Build 4


Read our JBL Flip 6 review

Also consider the JBL Charge 5

Read our review of the Ultimate Ears Wonderboom 2

Best Bluetooth speakers: portable speakers for every budget

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