It doesn’t take a sleuth of Sherlock Holmes’ stature to uncover the killer feature of the JBL Charge 3. The clue is in the name.
This portable Bluetooth speaker is blessed with a 6000mAh battery, which is darn impressive - even if its recently announced successor, the Charge 4, takes that to 7500mAh. It doesn’t just allow the speaker to tick over for the best part of 20 hours; it can also be used to resuscitate a flagging smartphone or tablet.
As long as you have the relevant USB cable to hand, you can connect your device to the USB socket on the back of the Charge 3 speaker and piggy-back the built-in battery.
The feature is by no means unique to the JBL Charge 3, and while it isn’t a game-changer, it isn’t the only string to this speaker’s bow.
The Charge 3 has been designed with portability in mind and fits neatly into the company’s existing speaker range. It’s larger than the petite JBL Flip and JBL Link 20 but not as hefty as the JBL Xtreme.
This makes the Charge 3 a good size for flinging in a rucksack and taking on your travels.
And thanks to its rugged design, the speaker travels extremely well. It looks robust and sturdy – and feels just as tough and hardy in hand.
This is definitely a speaker that could quite happily cope with an active camping weekend or beach holiday.
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The JBL is wrapped in a special protective fabric and available in a range of colours, which isn’t too dissimilar from that used on rivals such as the UE Boom 2.
This material, combined with the rest of the Charge 3’s design results in an IPX7-certified speaker, which should survive 30 minutes underwater at a maximum depth of one metre.
Handy to know if you’re cruising along in your kayak and it happens to fall overboard.
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The speaker sits on a built-in rubberised stand, which is punctuated by a small row of LED lights, which indicate battery life. The more lights lit, the longer the battery life left.
Follow the stand round to the back of the Charge 3 and you’ll see a rubber panel. Stick your nail in the gap, pull it away and there’s a selection of inputs lurking underneath.
There’s a 3.5mm socket for a more stable wired connection to your phone, and both a micro USB socket and a Type C USB socket for charging smartphones and the like.
Make sure the panel is put securely back in place, or else you could compromise its water-resistance.
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The feature count doesn’t stop here, though. There’s a built-in mic, which works with the speaker’s noise and echo-cancelling technology for hands-free calling.
You can also team up with other compatible JBL speakers to supersize your set-up. This is done by pressing the JBL Connect button and linking speakers together using the JBL Connect app, available for Android and iOS.
Press and hold the Bluetooth logo on top of the speaker and the Charge fires out a small tone to let you know it’s looking for your smartphone. It chirps again to acknowledge you’ve been paired up.
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Given the JBL’s rugged and sturdy build, you won’t be surprised to hear the Charge 3 sounds neither shy nor hesitant. It’s an enthusiastic, powerful sound, highlighted by the passive radiators pulsing vigorously at either end of the speaker.
They’re quite a mesmerising sight, but drag your attention away from them for a second and you’ll be able to appreciate the Charge’s energetic nature.
Stream Delphic’s Ppp over Bluetooth and the JBL Charge 3 has no issues with drive, as the tune pulses and pounds along.
The JBL’s closest rival is something like the UE Boom 2 (£120). Here, the JBL sounds more substantial and gives more weight and substance to voices and bass kicks.
Switch to the The Hills by The Weeknd, and the Charge 3 gets the emotion and pace of his vocal just right. Again, lows sound weighty and extremely powerful – the bassline extends and reaches down with the speaker showing an impressive level of control.
The UE equivalent sounds a touch more expressive in the midrange, but just isn’t capable of the same scale and authority that lends itself well to a portable outdoor-friendly speaker like the JBL.
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There’s no riddle where the JBL Charge 3 is concerned and the evidence speaks for itself.
It may not be the newest speaker in JBL's Charge family, but that doesn't stop it being a versatile wireless speaker with a fine feature set and very good sound quality. For its price (which has dropped since we first reviewed it), it is excellent.
See all our JBL reviews