Ultimate Ears Wonderboom 4 review: more bass than you bargained for

Deciding on the best speakers of the year is tricky business: between ultra-powerful, room-shaking speakers, and expensive hi-fi setups, it's undoubtedly difficult to figure out what truly is the greatest speaker of the year. A strong competitor for this title, however, might come from a low-budget, relatively small speaker with a lot to offer for a reasonable price: the Ultimate Ears Wonderboom 4.

A robust budget speaker built for portability, the deceivingly small Ultimate Ears Wonderboom 4 packs an incredible amount of bass and audio richness into its small size and reasonable budget, but how does it chalk up with its competition?

What's The Best had the pleasure of conducting a hands-on review of the Wonderboom 4, testing it on the go and throughout the home for an accurate look into this remarkable speaker that's full of surprises.

Ultimate Ears Wonderboom 4: first impressions and design

Upon the arrival of the Wonderboom 4, I was shocked at its size: at about the size of a standard coffee mug, with a little extra width, the Wonderboom 4 is small, which didn't give me a whole lot of hope for its sound.

A smaller speaker means less air pressure can build inside, so getting a booming, rumbling bass is less likely. Before even listening to music, I powered it up, and its pleasant startup noise startled me with its satisfying, bassy hum: I was in for a lot more bass than I bargained for.

Sound and bass: a budget speaker with high-end sound

The Wonderboom 4's powerful audio output and pleasing level of precision is a marvel of budget speaker technology, and its 360-degree sound quickly immerses large spaces, even the outdoors, with a gut-punching sound.

With a name like the Ultimate Ears Wonderboom 4, you'll hardly be surprised to learn that its shining feature has to be its bass, which is simply sublime. Powerful and detailed, without drowning out the intense, stinging high tones, it's truly unfathomable that this speaker is less than £100.

Sound modes and features

On the base of the speaker, lies a somewhat hidden feature: an 'Outdoor Mode' which sounds promising initially: more power to accommodate for limited surface reflections? Count me in.

It cranks up treble, but for us, it's a touch too much. Losing the speaker's fine balance in the process, it's certainly one of the more disappointing features of this speaker, and its 'Podcast Mode', activated by the same button, is almost certainly worse.

Again, the thought process behind a 'Podcast Mode' is considerate on Ultimate Ears' part: podcasts form a large part of people's day-to-day lives, but the idea of sharpening vocals for better clarity isn't without its flaws.

From my experience, the standard mode's warm bass and inviting sound lend far better to podcasts, where audio quality is rarely poor due to modern standards, which leaves the need for vocal sharpening utterly outdated.

Nitpicks aside, the Wonderboom 4 is a truly special speaker, not just made for bass-heads in need of a pulsing beat, but also for those who adore the warmth of jazz, the precision of classical, and the vocal perfection of pop music.

A deeper look into the Wonderboom 4's build quality

First and foremost, we have to praise the build quality of the Wonderboom 4: its simple, cylindrical design isn't a particularly innovative one, but in its simplicity, there's a sense of reassurance. The Wonderboom 4 has heft and weight to it, and nothing about it is remotely flimsy. Then there's its IP67 waterproof rating, protecting it completely against dust and up to a metre's depth of water without breaking, making it one of the sturdiest waterproof speakers of the year. As an added bonus: it's buoyant, so it's perfect for poolside listening.

The cylindrical shape, oversized volume buttons and clicky controls of the Wonderboom 4 are satisfying from the get-go, and the degree of control you have without requiring access to the connected phone is fantastic. They're also incredibly responsive, so controlling it has an instantaneous feel, which extends to its Bluetooth too, it's one of the faster speakers to connect to that I've used without question.

The stretchy band attached to the top of the speaker as an added touch is perfect for a carabiner attachment, making the Wonderboom 4 even more portable and space-efficient - snag this on to your backpack, and it has to be one of the finest outdoor Bluetooth speakers available for the price.

What makes the sound so good?

Though it's brilliantly robust, my love for the Wonderboom 4's sound outshines all other features, as it rightfully should. Housed within this moderately sized speaker is some of the most impressive, balanced sound I've enjoyed testing. Putting it through its paces with complex electronic music littered with rumbling bass, pin-sharp high frequencies and plenty of mid-tones, the Wonderboom 4 rarely faltered, even after hours of listening to music.

The gorgeous sound of the Wonderboom 4 cannot be understated: for less than £80, it is a wonder that such sound is achievable. I've been listening to Chet Baker Sings, and I must say it's been a particular stand-out experience for me since acquiring the speaker. The delightful warmth of Chet Baker's crooning, the slight crackle and imperfection of the recordings, and the harmonious plucking of the humming double bass – nothing is lost to the Wonderboom 4.

For those looking for great sound all day long, the Wonderboom 4 certainly doesn't disappoint. Many speakers claim a certain amount of battery life, only for it to fall flat, no pun intended, within a day of use. The Wonderboom 4 boasts a 14-hour battery life, and with moderate use, it'll last much longer than you'd expect. Using it fairly regularly over a week, even for use whilst watching films and television shows, the speaker soldiered on without any remote sign of an abrupt shutdown. I've yet to have rendered the speaker completely dead, and charging it for as little as 15-20 minutes gives it hours more use.

Unlike what we experienced with the Ultimate Ears Boom 4 speaker, the more expensive model, I've found the bass and balance to remain consistently strong throughout use, with no need to tweak its EQ app settings.

Overall design impressions: where might users be divided?

For most, the largest mediocre feature of the Wonderboom 4 is its fairly standard design. Like the Sony SRS-XB100 and other budget Bluetooth speakers alike, the rounded, cylindrical design, bright blue colour and fabric mesh aesthetic aren't anything outstanding, by any means.

That isn't to say it's a bad thing: it's a tried and tested design, assisting in its sturdiness and elements such as the fabric mesh dramatically improve its resistance to water and dust, but it's no revelatory improvement from its predecessor, the Wonderboom 3.

Any downsides?

The largest downsides to the Wonderboom 4 centre around its lacklustre 'Outdoor Mode' and 'Podcast Mode', which offer very little in strengthening the performance of the Wonderboom 4 in any conceivable way.

My first complaint about this feature, however, is just how hidden it is. Positioned at the very underside of the speaker itself, I remember hearing about the Wonderboom 4's 'Outdoor Mode' and was eager to try it, only for me to later presume it was connected to the Ultimate Ears app. Later, upon inspecting the box, I then realised there was a dedicated button for this feature.

In the shape of a small LED tree that glows white once activated, I had high hopes for this feature, largely due to just how appealing the design was, awkward as its positioning may be. I was quite quickly disappointed by just how unappealing the sound is when 'Outdoor Mode' is activated.

I used Chet Baker's gorgeous, soothing love songs as an example earlier, which sound so melodious on the speaker's primary mode, but when churned through its 'Outdoor Mode', I noticed a major decline in sound quality.

In an effort to squeeze as much volume as possible out of this palm-sized speaker, Ultimate Ears went a little too far in its pursuit for louder sound. Rough, sharp, and cracking, much like a low-end car radio: 'Outdoor Mode' is sadly, a disappointment.

And 'Podcast Mode' is even worse: sound is utterly muted in an attempt to isolate vocals, so I tested it with a podcast on 'Standard Mode' as well as 'Podcast Mode', and immediately noticed the weight of each unique voice became rough, losing all manner of bass and therefore presence.

Turning the Wonderboom 4's beautiful sound into a filtered, unrecognisable, almost grating sound, simply does a disservice to the speaker itself, which is a major shame.

Price and competition

One of the Wonderboom 4's strongest aspects has to be its price, and at less than £100, there's no wonder as to why. The sheer value of this bassy little speaker cannot be understated, the sound quality alone is unlike anything I've experienced in a budget speaker, but when paired with its tough design and slick useability, the Wonderboom 4 is elevated to new heights.

Its competitive price outshines most other budget Bluetooth speakers on the market in my opinion, with even the likes of Marshall, JBL and Sony being given a true run for their money. You might find its bass similar to what you might find in an infamously bassy Bose speaker. Yes, something like the Bose Soundlink Max might give it a run for its money in terms of quality, but at over quadruple the price, it's a much better deal for plenty of sound.

Who is it for?

The Ultimate Ears Wonderboom 4 is for those looking for a little extra bass at a lower price point. It's a great speaker for students considering its compact size and low price, and if you're constantly on the go, it helps to not carry a particularly weighty speaker on your travels.

This detail-rich speaker is packed with plenty of bass, so it's perfect for parties and social gatherings, and it retains its quality at lower volumes too. For audiophiles, backpackers and casual listeners alike, the reasonable price of the Wonderboom 4 makes it one of our favourites this year.

Would we recommend it?

Without question, the Wonderboom 4 is worthy of a strong recommendation: from its solid design, its robust build quality, a plethora of strong customisation options and much more, it's a brilliant all-around speaker for impressive audio for less than £100.

If you're looking for something a touch more outdoorsy, however, we'd certainly recommend avoiding the limited 'Outdoor Mode', as it offers very little in terms of improving performance. Yes, this speaker is designed to be used outdoors, but I've found it to be a lot better functionally inside, sat on a desk or in your lounge.

More items to consider

Who tested it?

The Ultimate Ears Wonderboom 4 was tested by Ryan Houghton, a veteran speaker tester and music enthusiast passionate about speaker technology. Amongst speakers, Ryan has also tested headphones, earbuds, soundbars and much more.

How was it tested?

The Wonderboom 4 was tested by using it as a replacement for my own speaker for over a week. From full charge, I did not charge it again. I watched television shows, films and listened to hours of music during work hours to get a better sense of how good the speaker really is.

Along with listening to the Wonderboom 4, I used its features, testing its connectivity, pause and play features, as well as its various modes.

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Ryan Houghton is a commercial content writer for What’s The Best, known best for his expertise in gaming, with a particular soft spot for PC gaming, audio tech, televisions and smartphones.

Diligently writing for What’s The Best for almost two years, there are very few tech products Ryan hasn’t had his hands on to review; televisions, headphones, folding phones and even LEGO, if it’s nerdy, he’ll be there.

His well-versed history as one of the resident techies at What’s The Best has kept him keen to uncover the very best deals, savings and offers for those in need of a cracking deal to upgrade their setup.

In his downtime, Ryan most likely has his nose buried in a fantasy book, or his eyes glued to a screen whilst playing a tough-as-nails Soulslike or leisurely RPG, indulging in most forms of escapism where possible.

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