Focal Mu-so Hekla Review: An All-In-One Atmos System That Feels Like Hi-Fi

The Mu-so Hekla looks like a soundbar. That is where the comparison ends. Focal and Naim packed 15 drivers, 660 watts of amplification, legitimate 30 Hz bass, Dolby Atmos, high-resolution streaming, and two distinct spatial-audio engines into one low-profile chassis.

Verdict

The Focal Mu-so Hekla looks like a soundbar. It goes beneath a TV or projection screen, stretches about 39 inches across, and contains the entire audio system in one chassis. But calling it a soundbar misses the point.

Most soundbars are built around convenience first, with fidelity and output negotiated around that goal. And they are typically slim and designed for wall mounting. The Hekla comes from the opposite direction. It is a proper system that sits upon a shelf.

Focal approached it as a loudspeaker company. Naim approached it as an electronics, amplification, and streaming company. Inside are three woofers, two midrange drivers, two tweeters, four side-firing full-range drivers, and four upward-firing drivers. Each gets dedicated amplification, with 60 watts per woofer and 40 watts each for the remaining 12 drivers. Total system power is 660 watts.

The specs help explain why the Hekla plays deeper, cleaner, and louder than its form factor suggests. It also explains the $3,600 price. This is the first all-in-one immersive system I have heard that I consider fully satisfying as a music system, all on its own. It is not a TV accessory that happens to play Spotify. It is a credible digital hi-fi system that also handles movies, television, and games.

The Hekla supports playback configurations up to 7.1.2. What matters is whether it produces a convincing three-dimensional sound field, which it does.

Room and Setup

The Hekla needs clear paths to the side walls and ceiling because its Sphere processing relies heavily on reflected sound. It works best centered between reasonably symmetrical walls, away from corners, with a flat ceiling and a wall-mounted display.

A freestanding TV can create two problems. It may physically block the upward-firing drivers, and its stand may force the Hekla too far forward or too low relative to the screen. A wall-mounted TV or projection screen is the natural partner.

Focal recommends positioning the system horizontally, with the tweeters roughly 10 to 28 inches above the floor. The listening position should ideally remain within about 13 feet, and the seat should not be too far from the rear wall. The exact numbers are less important than maintaining a room with useful reflective surfaces and sensible symmetry.

I evaluated the Hekla in two quite different spaces.

The first was my high-rise apartment, where its bass output and Dolby Night mode immediately became relevant. The second was Brian’s house, in a 15-by-29-foot living room—about 435 square feet, or 40.4 square meters. Focal describes Sphere modes as ideal for enclosed, acoustically treated rooms up to 40 square meters, so the room was essentially at the stated size threshold even though its open-plan layout differed from Focal’s ideal conditions.

The Hekla had no trouble filling it.

Brian’s display was a wall-mounted 85-inch Hisense. For the temporary setup, we placed the Hekla on its shipping carton above the coffee table to reduce the vertical gap between the speaker and TV. A permanent installation would use a credenza or shelf at the correct height. The carton visible in the photos and video is not a new Focal accessory.

That large-room test established two things quickly: the Hekla can generate full-on spatial audio across a substantial open floor plan, and its bass capability does not collapse when the room gets bigger.

ADAPT Room Tuning

Focal’s ADAPT process skips the usual sequence of chirps, sweeps, bleeps, and bloops.

Instead, it uses room geometry. You can enter distances manually or, with a compatible iPhone Pro model (iPhone 12 Pro or newer), use ADAPT’s augmented-reality camera measurement to identify the Hekla, listening position, walls, and ceiling. The app then uses those measurements to tailor timing and spatial rendering to the room.

I checked the camera-derived distances against physical measurements. They were accurate within an inch.

ADAPT is not the same thing as a conventional microphone-based room-correction system that automatically measures frequency response and sets every channel level. It primarily establishes spatial relationships. You still use the app’s level and effect controls to finish tuning by ear.

Switching ADAPT off and on produced a sound field that became simultaneously wider, more cohesive, and better balanced when correction was active.

The result is still significant. Switching ADAPT off and on produced a sound field that became simultaneously wider, more cohesive, and better balanced when correction was active. It did not sound like a tonal filter had been dropped over the system. The acoustic image simply snapped into better focus.

In my room, I preferred the bass EQ at -4 dB across all five listening modes. That adjustment did not make the Hekla sound lightweight. It brought the bottom end into proportion with the midrange and treble while leaving ample low-frequency impact.

Why the Design Matters

Hekla earns its luxury positioning before it makes a sound. The chassis is built from brushed, sandblasted, and anodized aluminum. Its finely perforated grille looks cleaner and more substantial than the fabric socks covering most soundbars. A ribbed aluminum heat sink runs across the back, dissipating heat from the Naim amplifiers.

The top panel contains Hekla’s signature rotary control. It looks like an oversized watch crown set into the chassis, and it behaves like one. The outer ring adjusts volume while the touch-sensitive center handles playback, source selection, favorites, Bluetooth, multiroom functions, and standby. A proximity sensor illuminates the controls.

The Hekla is deeper than it appears in photographs. At nearly 12 inches front to back, it needs a real credenza or shelf to sit upon.

That depth is part of the acoustic design. Focal needed enough internal volume for the three woofers, porting, amplification, processing, and the 15-driver array. It's what it takes to get near-full-range performance from a low-profile enclosure.

Measurements

I connected a laptop over HDMI and used Room EQ Wizard with a miniDSP UMIK-2 measurement microphone to examine the five listening modes, the tone controls, and the independent LFE adjustment. Measuring Hekla is less straightforward than measuring a conventional speaker.

In Sphere mode, the response arriving at the listening position comes from several drivers and multiple reflected paths. Even with upmixing disabled, side-firing drivers help establish the stereo image. A single on-axis trace cannot describe what the system is doing spatially.

The bass EQ measurement behaved predictably, reducing the broad low-frequency balance. During movie playback, the LFE adjustment audibly changed the deepest bass and effects intensity; that result is a listening observation rather than a conclusion drawn from the displayed L+R sweeps.

My preferred -4 dB bass setting landed where the listening suggested it should: the low end remained extended and powerful, but it stopped dominating the overall balance.

Mode-by-Mode Frequency Response

All six graphs use the same 20 Hz–20 kHz logarithmic frequency axis and 35–100 dB SPL scale, so absolute measured levels can be compared directly. The curves are not level-normalized. All six traces use REW 1/6-octave smoothing. These are in-room measurements, not anechoic loudspeaker data.

The measurements answered questions raised by the listening. Hekla’s remarkable bass is not a psychoacoustic parlor trick, and the app controls provide enough range to integrate that output with the room.

Listening

Dolby and Sphere

Hekla offers five primary listening modes:

• Dolby Movie
• Dolby Music
• Dolby Night
• Sphere Movie
• Sphere Music

These are not cosmetic presets.

The three Dolby modes use Dolby’s virtualized spatial processing. Their presentation tends to be tighter, more restrained, and more naturalistic. The immersive sweet spot is also relatively concentrated around one or two listeners.

Focal and Naim’s Sphere modes lean more aggressively on the side walls and ceiling, combining beamforming, crosstalk cancellation, and reflected sound. Sphere produces a wider listening area that works better across a three- or four-person sofa.

It is also more flamboyant. Dolby generally presents a mix with greater restraint. Sphere more readily expands it into the room. Sometimes that expansion is exactly what the material needs. Sometimes it introduces too much spatial seasoning.

Each mode gets its own controls. Depending on the mode, those include bass, midrange and treble EQ, loudness compensation, voice enhancement, LFE level, surround intensity, height intensity, and dynamic-range reduction. Sphere also provides a width adjustment and an upmixer switch.

Dolby generally presents a mix with greater restraint. Sphere more readily expands it into the room. Sometimes that expansion is exactly what the material needs. Sometimes it introduces too much spatial seasoning.

That flexibility matters because there is no universally correct setting. Different productions respond differently.

For movies, Dolby Movie was usually the safest choice. It delivered the most consistent tonal balance and preserved dialogue naturally.

Sphere Movie was more content-dependent. At its best, it created a larger and more involving acoustic bubble. With the wrong mix, it could exaggerate ambience or reverberation.

Music was less predictable. Some albums favored Dolby Music. Others came alive through Sphere Music.

Music

Stereo Without the Gimmicks

I started with New Order’s The Rest of New Order, including the “World (Perfecto Mix).” New Order’s production is precise and familiar. Each synth, drum-machine hit, bass line, and vocal has a particular job.

Sphere Music with the upmixer turned off was excellent.

The Hekla produced the kind of wide, stable soundstage expected from a good pair of conventional speakers. The image extended well beyond the chassis without turning into vague ambient wash. Instruments maintained their relative positions across the front.

Turning on the upmixer did not radically change the tonal balance. It opened access to the height, surround, and width controls, allowing me to dial in as much spatial expansion as the track could support.

New Order did not need the upmixer. It still sounded good with it.

That became the pattern. Hekla does not force every stereo recording into a synthetic Atmos spectacle. Sphere Music can retain a conventional front soundstage or stretch it around the room, depending on the settings.

Twilight Circus Dub Sound System’s Horsie provided one of the best stereo demonstrations. On “Dance,” the album’s second track, the bass line established the foundation while organ and percussion filled the space with fine textural detail.

Hekla does not force every stereo recording into a synthetic Atmos spectacle.

Upmixed through Sphere Music, it became one of the best renditions of that recording I have heard on any system. The sound field felt as tangible as what I expect from a properly configured AVR-based Atmos setup.

Nothing was left on the table.

Native Atmos Changes the Equation

The Orb and David Gilmour’s Metallic Spheres in Colour moved the Hekla into another category.

The Atmos mix is full of precisely positioned sounds, drifting textures, discrete samples, and effects that move without remaining tied to the front of the room. Sphere Music let the Hekla perform the disappearing act associated with good loudspeakers.
The sound stopped appearing to come from the chassis.

Individual elements occupied whatever point in the room the mix assigned to them. The presentation was fully three-dimensional, not simply wide or reverberant. Audio mirages appeared around and above the listening position with convincing specificity.
Switching to Dolby Music produced a notable change. The sound field contracted, the Hekla became easier to locate, and the presentation sounded somewhat boxier. Sphere Music created the more convincing illusion with this material.

That listening session changed how I think about the product. The Hekla is not merely an alternative to a soundbar. It points toward a possible future for stereo systems: one compact active device that handles conventional stereo, spatial upmixing, and native Atmos at a legitimately high level.

Other Atmos tracks reinforced the point.

Snoop Dogg’s “Gin and Juice” was not shy about using the room. Samples arrived from multiple directions while Snoop’s voice remained locked to the center.

The Ramones’ “I Wanna Be Sedated” used a much simpler mix. That simplicity highlighted Hekla’s ability to maintain traditional stereo imaging while Marky Ramone’s drums energized the Atmos channels. It was edgy without becoming harsh.

Prince’s “When Doves Cry” arrived as a layered, panoramic mural. Prince’s voice remained solid and present. The drums were tight, and the kick had physical weight.
Atmos takes music reproduction on Hekla beyond what a basic stereo system or conventional soundbar can do. Not every mix needs those tricks, but the good ones are compelling enough to change listening habits. I kept scrolling for the next track.

The Bass Is the Star

Then there is “Royals” by Lorde.

Well, dang.

The Hekla’s integrated bass system showed off properly. The low end sounded deeper, grander, and more visceral than I am accustomed to hearing from some systems equipped with large external subwoofers.

It was not only depth. The bass was tight, nimble, articulate, and properly aligned with the rest of the music. Lorde’s voice retained its sophistication and finesse while the low-frequency pulses acquired genuine physical presence. This track left nothing on the table.

GRiZ’s Future Funk Vol. 1 tested output and treble clarity. Cranked up, the Hekla became almost scary-loud. Raw synth textures cut through with razor-sharp definition, but the system avoided the brittle hardness that often appears when compact active speakers reach their limits.

At Brian’s house, I could turn it all the way up without worrying about shared walls. I heard no obvious clipping or harsh distortion. Some dynamic compression may appear at the system’s absolute ceiling, but Hekla reaches remarkably high output before that becomes relevant.

By that point, it is already louder than most people need.

Movies

Movies make a stronger case for immersive audio than music because they routinely place important information behind and above the viewer.

The Hekla reminded me what I had given up when I simplified my personal system to two channels.

Gravity remains a reference Atmos test. The long opening sequence combines drifting voices, radio communication, mechanical details, and deep thumps while the astronauts move around the Hubble Space Telescope.

The Hekla passed.

Voices floated freely instead of sticking to the enclosure. Bass arrived with appropriate weight. Small effects occupied believable positions around the listening area. The result recreated the sensation of being inside the scene rather than sitting in front of it.
Mortal Kombat II provided a different test: late-night apartment viewing.

Dolby Night handled its transitions from dialogue into large fight sequences with impressive intelligence. It reduced major peaks without thinning the sound, collapsing the spatial field, or burying quieter information. Dialogue remained intelligible, and the action retained enough scale to stay entertaining.

Dolby Night handled its transitions from dialogue into large fight sequences with impressive intelligence. This is what night mode should do.

That is what a night mode should do.

It does not simply turn everything down. It reduces the difference between quiet and loud material while preserving the shape of the presentation. For apartment and condo owners, this is a core feature rather than a bonus.

Large-Room Movie Tests

In Brian’s open-plan room, the race from Ready Player One delivered the expected thuds, impacts, and crunches. Raising the LFE effect produced genuine tactile bass, not merely audible low-frequency content.

The system also reached convincing movie-watching volume without the room swallowing its dynamics.

The opening number from The Greatest Showman highlighted the energy of the voices. The Hekla maintained the track’s theatrical momentum rather than flattening it into generalized loudness.

The Live Aid performance of “Radio Ga Ga” in Bohemian Rhapsody showed how sharply Dolby Movie and Sphere Movie can diverge.

Dolby sounded restrained but recognizable. The vocals maintained the familiar tonality of the performance, and the presentation felt more faithful to the mix.

Dolby is usually my starting point for movies, but Sphere is not an effect that can be dismissed after one comparison. The better choice depends on the mix.

Sphere created a larger stadium. It magnified the ambient reverberation and expanded the crowd atmosphere, but it also sounded more processed. Some listeners may prefer the spectacle. I preferred Dolby’s naturalism for this scene.

Deadpool & Wolverine flipped the result. Sphere sounded more relaxed, with dialogue that was less forward and less in-your-face.

This is why the mode controls matter. Dolby is usually my starting point for movies, but Sphere is not an effect that can be dismissed after one comparison. The better choice depends on the mix.

Dialogue intelligibility remained consistently high. The dedicated Voice Enhance control is available for anyone who needs more dialogue emphasis, but I rarely felt compelled to use much of it.

What the Hekla Gets Right

The defining achievement is integration. Hekla combines hi-fi clarity, deep bass, convincing spatial rendering, and enough output for a large room without sounding like a collection of separate tricks. Music, movies, television, and games all share the same tonal consistency and dynamic composure.

Full-Range Bass Without a Subwoofer

That statement gets thrown around in reviews of all-in-one systems, usually with an unspoken qualification: you do not need a subwoofer as long as you do not expect actual subwoofer performance.

Hekla is different.

Focal rates the Hekla at 30 Hz–20 kHz, ±3 dB, with a -6 dB point at 27 Hz. Those numbers place it comfortably into subwoofer territory for music and most movie content.

I connected a compact SVS subwoofer through the Hekla’s RCA output. The app allows selection of crossover frequency, making it possible to run Hekla down to 30 Hz and hand only the bottom octave to the external sub.

Switching between the SVS and Hekla running full-range produced remarkably little difference.

There are still reasons to add a subwoofer. A dedicated theater may demand meaningful output through the 16-to-30-Hz octave. Large rooms and listeners chasing extreme playback levels can also benefit.

Most of what changed could be attributed to level. Occasionally, the external sub appeared to reach slightly deeper, but Hekla’s own bass had the same tightness, articulation, and tactile quality. It could make bass physical. You felt it.

There are still reasons to add a subwoofer. A dedicated theater may demand meaningful output through the 16-to-30-Hz octave. Large rooms and listeners chasing extreme playback levels can also benefit.

For typical music and living-room theater use, it is optional.

Integration could be easier. Hekla does not provide a subwoofer calibration tone, so matching external-sub level requires measurements or repeated listening. During Deadpool & Wolverine, the external sub sounded somewhat disconnected in Dolby Movie. Turning it off restored a more cohesive balance, and I did not miss the added hardware.

The internal bass section was already taking care of business.

Living With It

App, Inputs, and Everyday Control

The Focal & Naim app is central to the experience.

Hekla has no dedicated handheld remote. HDMI CEC lets a compatible TV remote control volume during normal viewing, and the top-panel dial covers basic operation, but deeper adjustments require the app.

My recommendation is simple: dedicate an iPad mini to the system. It becomes the best remote Hekla does not include. The larger screen makes real-time comparisons between sound modes and spatial settings far easier than working from a phone.

The app is logically organized and responsive. More importantly, its adjustments are persistent by source. HDMI can retain one sound mode and set of adjustments, optical another, Spotify another, Bluetooth another, and so on.

That may be Hekla’s coolest functional feature.

You do not have to restore your preferred movie settings every time you return from music streaming. After some initial experimentation, the system starts behaving as though it knows what you want from each source.

Wired connectivity is intentionally limited. There is one HDMI eARC connection, one optical input, Ethernet, and an RCA output pair for a subwoofer. The RCA jacks are outputs, not analog inputs. You cannot connect a turntable directly.

Optical is useful for legacy digital sources, but it does not carry Dolby Atmos. HDMI eARC or compatible network streaming is the route for immersive formats.

Wireless support is far broader, including AirPlay 2, Google Cast, Bluetooth, UPnP, Spotify Connect, Tidal Connect, Qobuz Connect, and internet radio. Hekla also participates in Focal and Naim multiroom systems.

Who It Is For

Here is the catch: Hekla does not do analog. It does not include a conventional remote. It does not accept optional wireless surrounds. Focal does not list DTS among its supported formats. It is not designed to hang under a television, and it is not a natural fit for a freestanding TV on a narrow console.

It wants its own perch.

It also wants a room with useful side walls, a flat ceiling, and enough symmetry for reflected sound to do its job. Missing walls, vaulted ceilings, severe asymmetry, and corner placement all reduce what Sphere can accomplish.

Those are real restrictions.

They also reveal the design philosophy. In high-end audio, simplifying a product often means removing features so that the remaining ones can receive more attention. Hekla trades universal connectivity and modular expansion for better drivers, stronger amplification, serious bass, high-quality construction, and tightly integrated processing.

You are buying quality and simplicity engineered for performance.

For modern listening habits, AirPlay, HDMI eARC, Tidal, Qobuz, and Spotify will matter more to many owners than a direct phono input. Other buyers will see the lack of analog connectivity as a deal-breaker. Both reactions are reasonable.

You are buying quality and simplicity engineered for performance.

The ideal owner has a wall-mounted TV or projection screen, values music as much as movies, wants Atmos without speaker clutter, and has no interest in running wire around the room.

An urban apartment or condo may be Hekla’s natural habitat. It saves space, looks appropriate in a carefully designed living room, produces more bass than most neighbors will appreciate, and includes one of the best night modes I have used.

Final Take

The Focal Mu-so Hekla surprised me. I expected impressive construction, polished software, and competent sound. Focal and Naim have enough history that anything less would have been strange.

I did not expect this degree of fidelity, this level of sonic transparency, or bass this deep and controlled from such a low-key device.

Hekla does what expensive speakers are supposed to do. It teases out detail, preserves tonal character, builds a soundstage larger than itself, and disappears when the recording allows it. Then it switches roles and delivers convincing Atmos envelopment for a movie or game.

It is not cheap. At $3,600, it competes with serious component systems.

But price out the speakers, amplification, streamer, subwoofer, room processing, cabling, and furniture needed to equal its total capability. Then account for the space and installation. The value proposition changes quickly.

I did not expect this degree of fidelity, this level of sonic transparency, or bass this deep and controlled from such a low-key device.

You can build something bigger. You can build something that plays deeper, louder, and with more precisely localized rear-channel effects. It will involve more equipment, more wiring, more setup, and quite possibly more money.

Hekla offers a complete Atmos experience without that hassle. In some respects, it is simpler than a soundbar because there is no external subwoofer or satellite pairing to manage. This is the first all-in-one immersive system I have heard that I would choose as a primary music system rather than tolerate as a compromise.

The Focal Mu-so Hekla is a credible hi-fi, a convincing home theater, and one of the clearest demonstrations yet of where active spatial-audio systems are headed. Highly recommended.

By Mark Henninger, ProjectorScreen.com

Chief Technical Editor • THX Level II Certified Video Calibrator

Mark Henninger is a veteran AV journalist and image specialist whose professional photo and video work shaped his expertise in image evaluation and color accuracy. He built AVS Forum's editorial review program and served as the site's editor, applying a THX-trained calibrator's discipline to reviews of displays, projectors, and audio systems. He later specialized in projector reviews—especially UST models—at ProjectorCentral before becoming editor of Sound & Vision magazine.