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Plenty of speakers can fill a room with sound. That’s sort of their whole point. Far fewer speakers have an organic presence before they’re even turned on. That’s sort of the Devialet Phantom Ultimate 108 dB’s whole thing. Originally debuted in 2015 and purposefully refined for a decade, these Parisian-produced wireless speakers dominate the conversation from whatever perch they occupy. In a landscape populated by the KEF LS50 Wireless II’s coaxial composure and the JBL 4329P’s studio-bred punch, the Devialet Phantom’s improbable profile doesn’t fit in. Nor does it want to. What this $3,800 outlier does want is to prove that its sculptural enclosure can dominate audibly as well as it does visually. With a name that is part promise, part warning, the Devialet Phantom Ultimate 108 dB is the latest iteration of a powered speaker for those who appreciate sonic ambition and industrial design equally. Now with even more toned muscle.

The build

A semi-spherical statement that’s one part whimsy, two parts woofers, the Devialet Phantom Ultimate 108 dB is somewhere between a cybernetic eyeball and a Bubble Ship from the 2013 sci-fi movie Oblivion. There are no boxy cabinet edges. No rectangular grilles. No classic cues of any sort. This is a high-gloss sealed ovoid engineered around 1,100 watts of Devialet’s proprietary ADH (Analog Digital Hybrid) amplification, paired with SAM (Speaker Active Matching) and AVL (Adaptive Volume Level) processing to maintain scale regardless of playback level. All these pulsations and calculations are guided by Devialet’s next-gen. NXP i.MX 8M Nano 4 x 1.5 GHz SoC.

Adorning the front of this curved composite body is an acoustically transparent grille that visually references French formal gardens and structurally guards a redesigned aluminum dome tweeter nestled in an aluminum midrange dome. Opposing ABS-dome woofers flank the body, their outward excursion handled by HBI (Heart Bass Implosion). The Phantom Ultimate’s acoustic engineering is backed by a lot of acronyms and even more patents [over 200, according to Devialet’s website]. Externally, optional Ethernet and optical connections are located beside the recessed power port, as a wall socket, though no external amp, is required. And touch controls adorn the top rear. But with a Wi-Fi 6, 32-bit/96 kHz streaming engine that supports AirPlay 2, Google Cast, Spotify Connect, TIDAL Connect, UPnP, and Roon, plus Bluetooth 5.3 just for good measure, Devialet’s app is the more likely means of interaction. [It’s even required for initial setup.]

Available in Deep Forest or Light Pearl, the Phantom Ultimate has a silhouette that contrasts with traditional furnishings, but the ultra-matte finishes with mirror-polished accents that are much more forgiving for color palettes, though not fingerprints. [That statement is perhaps less accurate for the more expensive, Moon Gold-gilded Opéra de Paris edition.] Compared to the stand-mounted stereo considerations of the KEF LS50 Wireless II and the pro-audio pragmatism of the horn-loaded compression driver and tactile knobs on the JBL 4329P or its little brother, the JBL 4305P, the Phantom Ultimate invites a more centralized, less optimized display. Perhaps the most similarly singular chassis would be the Bowers & Wilkins Zeppelin Pro with its lifestyle-forward glide. But even that has a recognizably buoyant outline and fabric familiarity compared to the Phantom Ultimate’s pneumatic capsule [which weighs 24.5 lbs. and measures 9.7 in (wide) x 13.5 in (deep) x 9.7 in (tall) for those eagerly clearing space … a “portable speaker” this is not].

The sound

I tested these speakers solo and synced, via Wi-Fi 6 and Ethernet connections. I experienced only a couple of wireless stutters when paired, and only when really taxing my network with multiroom devices, but I would always recommend hardwiring if/when possible.

On its own, Devialet’s Phantom Ultimate 108 dB is an experience. In a pair, it’s an event. Each Phantom Ultimate uses a robust Class A stage to shape the signal and Class D amplification to further drive it, with pressure management in place so the speakers can operate with minimal distortion no matter how they’re pushed. And pushed they can be, spanning 14-35,000 Hz and reaching up to 108 dB SPL at 1 meter, as promised by the product name. Why you’d need to test such high-energy output is beyond me, but I recently downsized from my villa in Provence to a loft in Crystal City, Virginia, so …

Nothing prepares you for the Phantom Ultimate’s sub bass authority. I have a pair of GoldenEar T66 tower speakers in the same room—each containing powered 500W subwoofers with radiators capable of achieving 29 Hz—and I was more shocked by the perceivably articulate, potentially infrasonic bass of the Phantom Ultimate. Yet despite its capacity for impact, the Phantom Ultimate never appeared to oversaturate the midbass or swallow the details. Immersive midrange surges forward, while shimmery treble traces edges rather than softening them.

Regardless of genre—and I played everything from synth-pop to shoegaze, atmospheric black metal to psychedelic soul—the Phantom Ultimate delivered gripping drama. Even the busiest passages and most gnarled textures were presented with little smearing. The Phantom Ultimate projects a coherent soundstage that’s tight and expressive rather than merely explosive, though it can be that, too, fed some booming 808s or a pumping sidechain. While not clinical, the high end can reveal glare if it’s present. It’s not fatiguing so much as inherently favoring lively propulsion over smoothly polished. And it can convey emotion at more polite, less physical levels of performance.

I used the Phantom Ultimate on the stands I use for testing most bookshelf speakers, which sit 30 inches off the ground and a foot from the wall—somewhat in line with Devialet’s recommendation of upturned trajectory. But Devialet also sells an even lower-to-the-ground $349 Treepop (tripod) Stand that matches the speaker’s finishes and oblong base, as well as a more vertical $399 Tree Smart Stand.

The conclusion

If your preference is for organic warmth and silky, accommodating timbre, you won’t find it with the Devialet Phantom Ultimate 108 dB wireless speaker. There is nothing passive about the signal path. But vertical integration and active governance aren’t bad things. With DAC, amp, and driver unified in their tuning and timing, there’s no ambiguity about synergy. And this ensures rhythms hit with precision and intention. There are other powered speakers that are neutrality-first monitors or have superior imaging, ranging from holographic to immediate. But few deliver the overall density. The latest revision of the Phantom is its most composed, most mature. It asserts rather than vanishes. It’s an adacious spectacle with a heightened sense of gradient control. One speaker can fill a good-sized room with architectural exuberance. A proper symmetrical pair unlocks tonal contours that truly do these shapely constructs proud.

[There is a $1,900 Devialet Phantom Ultimate 98 dB available for those with even less space for speakers or desire to expose their guilty pleasures to anyone that shares a structural surface, but we didn’t test that one.]

 

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