Ultimate Ears MEGABOOM 4 Review: The 360 Claim Does Not Hold

Ultimate Ears sells the MEGABOOM 4 on 360-degree sound. Both of the independent tests we hold for it reach the same conclusion about that claim, and it is not the one on the box.

The rest of the picture is more complicated, because on the actual sound quality — and on how long the battery lasts — our two sources disagree substantially. This review reports the disagreement rather than picking a side.

This is the most useful thing to know before buying, and it is the one thing both tests agree on completely.

The MEGABOOM 4 has two active drivers, mounted on the sides, with two passive radiators front and back. One test spelled out the arithmetic: genuine 360-degree reproduction would need at least four active drivers — front, back, left and right — and this has two. The consequence is that standing in front of the speaker you do not hear all the frequencies, because the drivers are not facing you. Move to the side and the sound opens up, but then you are listening to only the left or the right channel, not both.

The other test reached the same place from a different direction, finding the presentation extremely dependent on where you sit: a downward-sloping response directly in front with some masking effects, and a more sparkling sound once you move into the axis of one of the drivers. Its conclusion was that the architecture allows neither a natural stereo image nor a successful 360-degree effect.

There is a related practical restriction: the speaker is designed to stand upright. Lay it on its side and one of the drivers is blocked, so you lose part of the output.

Both tests agree the low end is the crux. They do not agree on the answer.

The first found a genuinely good bass extension — not a bass monster, but enough to give real foundation to the listening. It described the speaker as having a playful personality that only rarely overflows, avoiding aggression, with a healthy reserve of power. Its technical criticism was specific: an audible discontinuity between the drivers, which push a peak in the lower mids that gives the speaker its punch, and the passive radiators, whose resonance appears below 80 Hz. That mismatch brings a rise in distortion around 100 Hz, though it judged this not especially troublesome.

The second test was far harsher. It found the reproduction flat and lacking flavour, and concluded the bass is scarcely better than the smaller Boom 4 despite the larger cabinet — the drivers being too small and not well enough motorised, and struggling all the more because Ultimate Ears paired them with larger, more flexible passive radiators. It grants that the MEGABOOM plays louder in the bass than the Boom, but calls the result poorly structured, with neither roundness nor depth.

On the mids and treble the two are closer. The second test found the tonal balance not unpleasant and the mid and high frequencies rather well placed — with the important caveat that this applies when listening from the side. At moderate volume the balance is good but the highs are recessed, precisely because the drivers point sideways. The quoted maximum of 90 dB at one metre is reached, but only around voice frequencies of 300 to 400 Hz; at full volume it found the sound unbalanced and aggressive.

On dynamics the two converge again, unhelpfully for the speaker. The first called detail and dynamics nothing exceptional and the soundstage wide but lacking depth from the front and blurry towards the sides. The second was blunter, finding a lack of drive that produces an anaemic sound in which the layers are compressed and everything ends up sounding much the same.

Ultimate Ears quotes 20 hours. Our two sources tested it at the same 50% volume level and got materially different answers.

One measured close to 30 hours and called it a considerable score and a clear improvement on the previous generation. The other measured a little over 21 hours, describing that as confirming the manufacturer's promise and slightly exceeding it.

We cannot reconcile a nine-hour gap and we are not going to average it away. What both results support is that the speaker meets or beats its 20-hour claim; how far beyond that you get is unresolved. Charging is over USB-C, hidden behind a waterproof flap at the base — this generation's headline change, driven by the switch to USB-C across consumer electronics.

Here there is no dispute. The MEGABOOM 4 is a cylinder of about 87 mm diameter and 225 mm tall, weighing 935 g, in black, cobalt blue, raspberry red or lilac.

The polymer structure is wrapped in a fabric covering that is pleasant to the touch, framed by a silicone base and top plate that add drop resistance. It is rated IP67, so it survives dust and immersion, and it floats — though one test notes that while floating the drivers sit partly submerged and the sound is muffled. It is built to take knocks as well as water.

Two design gripes. The suspension loop is too small to get a finger through, which undermines the point of having one. And at 935 g this is a transportable speaker rather than a truly portable one — the smaller Boom 4 is the better choice for small hands or for slipping into a bag.

This is where the MEGABOOM 4 asks you to accept less than rivals offer, and you should know exactly what is missing.

There is no input of any kind beyond the charging port. No aux, nothing. If Bluetooth will not do, this speaker will not work for you.

Also absent: no microphone and therefore no hands-free calling or voice assistant, no multipoint, no fast pairing, no LE Audio and no Auracast. The codec is SBC only, though one test reasonably observed that codec differences are barely perceptible on a speaker of this class.

What you do get is solid fundamentals. Bluetooth is implemented seriously, with excellent connection stability and very good range. The module is Class 1 with a theoretical 45 metres — a genuine advantage on paper, but one that needs a Class 1 source to exploit, and most phones use Class 2 chips, so in practice you will not see it without a suitable computer and adapter. In ordinary domestic use the connection holds through normal obstacles without dropouts or quality loss. Gamers will notice a slight lag between picture and sound; ordinary video playback stays properly synchronised.

Multi-speaker pairing is handled by Ultimate Ears' own PartyUp, which works with older generations of UE speakers as well.

Control is a strong point and both tests say so. The huge volume buttons run down the front — though they can only be pressed in the centre — and the top panel carries three backlit buttons under a soft silicone covering for playback, launching a playlist and linking to other UE speakers. There is a power button, and a pairing button hidden a little too well behind its own indicator light.

The virtue is simplicity: even a first-time user is unlikely to get lost, and the audio and light prompts are discreet but clear.

The UE Boom app follows the same philosophy. It adds a parametric equaliser, shortcuts to streaming services assigned to the configurable multifunction button — with more options on Android than on other systems — and speaker synchronisation. There is also a megaphone function that turns your phone into a wireless microphone and projects your voice through the speaker. Both tests treat it as a novelty of limited use.

Buy it if you want a tough, waterproof speaker that will survive a beach, a shower or a pool, if you value simple controls over features, and if you already own UE speakers to pair it with. The build quality and the ruggedness are not in dispute, and the battery beats its claim on both tests.

Look elsewhere if you were buying for the 360-degree sound, because neither test found it delivered. Look elsewhere too if you need an aux input, a microphone, multipoint or fast pairing, or if sound quality is your first priority — one of our two sources rated it powerful and versatile, but the other rated it disappointing, and that is a real risk to weigh. Both tests point towards the smaller Boom 4 as the more practical size, and the second suggested that similarly priced rivals such as the JBL Charge 5 and the Beats Pill are more lively and musical.

Truthful Reviews has not tested this speaker. The measurements and findings above — the distortion rise around 100 Hz, the sub-80 Hz radiator resonance, the 90 dB maximum, and both battery results — are published results from two independent European technology publications on our approved source list, one of which states its review sample was loaned by the manufacturer. Both tested this exact model. Both source URLs are stored as this page's editorial provenance, and the disagreements between them are recorded rather than resolved.

We are not quoting a UK price. When we checked Amazon UK on 2 August 2026, the listing for the exact model showed only four units left and the buy box was held by Amazon Resale — open-box stock rather than new — with no new featured offer and no price displayed. Under our rules we omit a price rather than publish one we cannot stand behind. The MEGABOOM 3, BOOM 4, WONDERBOOM 4, EVERBOOM and MINIROLL are different speakers and none was substituted.

Check Amazon UK availability or search Amazon US.