Brane X smart speaker review: Boom without the bust

Don’t be misled by the Brane X portable speaker’s modest appearance. While diminutive and stealthy in style, this seemingly mild-mannered Bluetooth and streaming speaker is a kick-ass techno wonder that transforms into a sonic superhero faster than you can say “Shazam.” Or more appropriately here, “Alexa.”

First shown at CES 2023, the Brane X features a driver the manufacturer says represents “the most significant innovation in audio driver in a century.” Dubbed R.A.D. (the acronym stands for Repel-Attract Driver), the Brane X delivers levels of sub-bass more typically associated with loudspeakers reinforced by a discrete subwoofer and megawatts of power.

No one-trick pony, the Brane X also stomps the competition by delivering a surprisingly distinct, true stereo impression you almost never hear from a single-box speaker.

The Brane X is a cute little 7.7-pound thing, humming on 200-plus watts of Class D amplification. It can rock out as royally loud as a three-times-heavier, roll-about party speaker like the Sony SRS-XV800–minus the strobing light show. Far more importantly, the Brane X brings home those deep, chewy bass notes—digging all the way down to 20Hz—that drive so much of the drama in today’s chart-dominating hip hop and pop productions that get shortchanged by every other portable speaker in its size and weight class.

This review is part of TechHive’s in-depth coverage of the best smart speakers and the best Bluetooth speakers.

And the Brane X’s skills have been fine-tuned for critical listeners as well as party animals. If your dwelling is tight on space, this thing could satisfy as your only sound system.

Comparing the performance of a $599 Brane X with that of the similarly sized $449 Sonos Move 2 and the $350 Ultimate Ears Epicboom is telling. Tracking through the deluxe edition of SZA’s borderless breakthrough set Ctrl, there wasn’t a single deep bass and drum-emphatic track—from “The Weekend to “Anything”—that didn’t sound bigger or better on the Brane X. Ditto with rock artiste Peter Gabriel’s long-awaited new album, I/O. The album’s polyrhythmic, global-reach incantations sounded spectacular here.

More of an unplugged music fan? The Brane X’s basso profundo also imbues an extra umph of presence in music as diverse as folk, jazz, and even classical. It worked wonders for me with everything from Keb Mo’s funky Blues/Americana gem Good To Be to Jason Campbell and Azniv’s ultra-mod, offbeat New Opera.

To keep it real, I gottta say the Sonos Move 2 oft delivered a slightly more relaxed, airily open sound in my listening comparisons, while UE’s Epicboom proved best at piercing the fog with high-frequency clarity—at least after I’d tweaked each speaker’s EQ settings. But the Brane X is the affable buddy I’ve most wanted to tote around the house. It’s more fun to be with, the warmest, most personable, and dynamically energizing music purveyor, thanks in large measure to that added octave or two of tactile bass response, relative to the competition. (As radio preachers used to urge: “Put your hands on the speaker and you’ll truly feel the power!”

Design & build

Why has no one ‘til now fitted a large driver in a cabinet as compact as these rebels are using? Brane fit an 8-inch high-excursion subwoofer in an enclosure measuring just 6.1 x  9.3 x  7 inches(HxWxD).

Squeezing an 8-inch driver, plus a high-wattage amp (necessary to motivate a cramped driver), in a small enclosure is normally asking for trouble. It would create excess internal cabinet pressure and heat that could blow that speaker up, as Brane’s CEO Joe Pinkerton explained.

To sidestep those spoilers, the Brane X’s subwoofer relies on a radically designed voice coil that puts the moves on the backside of Brane’s semi-rigid carbon-fiber speaker membrane. The R.A.D.’s copper winding core is half the normal size and is supplanted with four tiny magnets affixed to a moving bearing. The designers call it a magnetic negative spring. Said bearing maintains precise centering (and sonic refinement) behind the speaker membrane with help from a sophisticated position-tracking/shifting mechanism (you can kinda see it hiding under the white cap in my rear-view image).

In the spirit of noise-cancelling headphone tech, which utilizes countervailing forces to make unwanted stuff disappear, the R.A.D. tech interacts with the core’s stationary magnet to effectively cancel compression force (aka back pressure). In the process, it keeps the speaker running cool–and so efficiently that it performs with just one-tenth the power demanded by a same size old-school woofer, according to Brane.

The tweaking starts the moment you turn on the Brane box and hear a little pumping noise. That’s the onboard air pump equalizing the internal pressure and placing the subwoofer’s driving mechanism in its optimal operating position relative to the membrane at the front. Lots more electro-magnetic magic is happening here; but frankly, that stuff is beyond my pay grade to explain.

I can say that when it’s fed hotly recorded (and delivered) content, I’ve clocked the Brane X barking at peak sound pressure levels up to 110-117 dB. That’s 10- to 15 dB higher than I could coax from the Sonos Move 2 or Ultimate Ears Epicboom, as measured on my trusty old Realistic Sound Level Meter. Brane’s VP of Engineering Dave Badger told me that the clocked decibel gap would have been even greater—giving the Brane X a bass zone advantage of 30 dB—had I used a band-sensitive SPL meter that tracked just the deep note extensions this thing is summoning up in the 20- to 60Hz frequency range. That’s no-man’s land for other small speakers.

With extra robustness comes some trade-off in battery run time, relative to the competition. With the bass set on “medium,” my preference, and the volume cranking at a moderately loud but comfortable 85 dB, I’ve been extracting about 12 hours of musical entertainment out of the Brane X. Recharging is done in three hours with a customized outboard power brick weighing in with its connecting cables at 1 pound, 4 ounces. Without the serious energy demands of a subwoofer, a second-gen Sonos Move 2 clocks upwards of 24 hours play on a battery charge (vs. 11 hours for the original Move), while an Epicboom delivers a run time of 17 hours.

No one-trick pony, the Brane X also stomps the competition by delivering a surprisingly distinct, true stereo impression you’ll almost never hear from a single-box speaker. It’s another reason why this thing could arguably serve as your one-and-only sound system.

Helping the cause, the Brane X’s design has four other drivers: two front-firing 0.75-inch silk dome tweeters, and two angled-out 2.5-inch metal dome midrange drivers. In comparison, the Move 2 and the Epicboom each pack stereo tweeters and just one midrange/woofer unit. The Brane X’s bass notes cross over from its subwoofer to its mid-range at between 150- and 180Hz. High-frequency reproduction transitions from the mids to the tweeters more gradually, at between 2- and 3kHz.

Listening tests

The extra clarity and dynamics the Brane X’s double midrange driver set delivers was a shocker in my listening tests, even on such early stereo recordings as “Lester Leaps in,” performed by composer/sax legend Illinois Jacquet with Kenny Burrell. And it brought home the Rolling Stones’ greatest hit, “Sympathy for the Devil,” in scary-good “persuasive-percussion” fashion. Nicky Hopkins’ barrelhouse piano lines (on the left) duking it out with Rocky Dijon’s and Bill Wyman’s voodoo conga and shekere beats emanating stage right.

When I auditioned the same song on the three-driver Sonos Move 2, the presentation felt flat by comparison. The stereo split was barely noticeable, and the summed monaural mid-range/low-frequency driver cancelled out about 80 percent of the piano’s presence, suggesting Hopkins’ part had been recorded out of phase, intentionally or not. The three-speaker Epicboom deliver better stereo separation, though not as well as the Brane X.

If only the Brane X’s silk dome tweeters were as impressive as its mid-range drivers and subwoofer. With content where a singer or player gets really close to the microphone, I’ve found the Brane X’s tweeters sometimes hit their limit and protest, making the performances sound a tad raspy. This bothered me with Jan Garbarek’s sax-soloing on the Keith Jarrett & Belonging track “‘Long As You Know You’re Living Yours,” which is one of my favorite torture tests when evaluating speakers. I also noticed excess graininess—compounded by intentional studio “sweetening”—in Jerry Garcia’s vinylized vocals on the classic Workingman’s Dead LP, played to the Brane X through its line-level input from an Audio-Technica LP-60X turntable.  

My critical ears have also detected a higher degree of generalized peak distortion when I cranked the Brane X extra loud, past 100 dB, although I suspect party-hearty types wouldn’t notice or mind.

After 40-plus hours of break-in, the Brane X tweeters have relaxed some, and I’m hoping that will continue just a bit longer. Using the Brane app to tamp down the top two EQ bands (centered at 3,000- and 12,000 Hz) by a notch or two also makes the pain subside. As does just keeping the volume at a more temperate level; say, in the 85- to 90 dB range.

If you’re a true high-roller, another option is to spread the load around by feeding your music source to a gang of Brane X speakers. Up to four can play in sync (and somehow in “surround,” according to Brane’s marketing). If you’re sourcing your content on an Apple product, you could also utilize Airplay 2 to stream to the Brane X and other Airplay-compatible speakers (personally, my Wi-Fi can’t handle more than two).

This being a portable speaker, you’ll also be wanting to enjoy music away from Wi-Fi networks. The Brane X offers Bluetooth 5.1 connectivity for that.

Streaming service compatibility

When Brane first announced this speaker’s full specs, I was delighted to see its streaming service options would include Spotify Connect, Pandora, Amazon Prime Music, SiriusXM, iHeart Radio, Deezer, and TuneIn. At present, only Spotify Connect earns a minimalist appearance in the Brane iOS and Android app. Tap on it and go to Spotify’s own home page.

“We have to walk before we can run,” said Brane’s Pinkerton, explaining the lack of support for other services compared to its larger competitors. “We built this speaker with a team of 10. Sonos employs more than a thousand people. Be patient. Upgrades are coming.”

There’s really no need to hold your breath. The other streaming services Brane name-checks can all be accessed via Amazon Alexa. Just register your streaming accounts in the Alexa app, and then shout your request to the Brane X’s four-microphone array. The speaker’s documentation says you don’t need to specify the app by name, but I found that to be essential with SiriusXM, because the service gives some channels generic names like “Real Jazz” or “Happy Rock” that confuses Alexa. Also worth mentioning: Pinkerton told me the Brane X supports high-resolution audio, but it currently limits streaming services to a maximum sampling rate of 16-bit/48kHz.

You might have noticed that Apple Music is not on Brane’s favored-nations list. Don’t worry, it’s easy to stream Apple content from an iPhone, iPad, or Mac to the Brane X via AirPlay—just tap the AirPlay icon at the bottom of your music app’s screen and then select the speaker as the output device.

Minor gripes

It’s mildly annoying that Brane’s app can store only one custom or default EQ contour. I’d like to be able to map, store, and quickly access different EQs for indoor and outdoor use, lower-res and higher-res content, and more.

The Brane app has no pause/play or volume-changing capabilities, either; you need to use voice commands or rely on your mobile device’s streaming app for those functions.

A 6-button capacitive (thermal) touch panel atop the speaker activates just the essentials. From left to right, light touches enable a Bluetooth/Wi-Fi connection, modify the deep bass (three steps), crank the volume down or up. There’s also a microphone mute button and a tiny dot that, when tapped, temporarily mutes the music and then summons Alexa, so you don’t need to shout the wake word.

Whether for aesthetic reasons or just to prevent accidental shut-offs, the Brane X’s power button is located on the back side of the speaker. Fishing for it isn’t always fun. There’s also a DC port back there to connect to power, and a 3.5mm audio input that seizes command of the show whenever you plug a product in. There’s no way to switch between wireless and plugged-in sources. I’d also like to see that remedied in a software upgrade.

I suspect locating the power connector, aux input, and power switch in a row there might also be part of Brane’s weatherproofing effort: The Brane X is rated IP57, meaning it’s sufficiently protected from dust to prevent failure, and that it can survive submersion in 1 meter of water for up to 30 minutes. We’ll tell you everything you need to know about IP codes at the preceding link.

Should you buy a Brane X smart speaker?

The Brane X is a miracle of applied physics, electro-magnetic engineering, and component miniaturization that will impress audiophiles, mainstream music lovers, bass-heavy headphone enthusiasts, and fans of car stereo rigs with chassis-rattling subwoofers.

It simply knocks the stuffing out of its competitors.