Focal Stella Utopia EM Evo Loudspeaker

Focal calls its second-from-the-top Stella Utopia EM Evo ($149,998 pair) a technological twin sister to its topmost Grande Utopia EM Evo because of its implementation of similar features. The Stella shares the Grande’s high-efficiency field-coil or electro-magnetic (EM) woofer, TMD (Tuned Mass Damper) driver suspension, NIC (Neutral Inductance Circuit), MRR (Machined Reinforced Rings), “W” sandwich composite cone material, Power Flower magnet structure, Focus Time driver alignment, and OPC+ filtering, multi-adjustment sound-personalization in a three-way design with more svelte dimensions than the larger four-way Grande.

Being a three way, the Stella has crossovers at 230Hz and 2.2kHz. The speaker has a single 13″ electro-magnetic woofer, a 1″ beryllium inverted-dome tweeter, and dual 6.5″ midrange drivers. The midrange and tweeter are in a physical midrange-tweeter-midrange (MTM) arrangement, sitting above the EM woofer’s enclosure.

The Stella has visually attractive curved surfaces on all four sides. Each driver is mounted in its own optimized semi-separate chamber, arranged in what Focal calls Focus Time—a mechanical system that aligns the phase between drivers at the listening position. This is accomplished with the woofer module having an ever-so-gentle backwards tilt, with the lower midrange module near parallel, the tweeter module slightly tilted downward, and the upper-midrange module tilted a bit more downward. The resulting look gives the modules the appearance of being gracefully curved, like a spine. When properly set up, the Stella’s module alignment better time-aligns the drivers’ outputs at the listening position.

Internally, the Stella’s cabinet is made of medium-density fiberboard (MDF) up to 2″ thick in key areas and heavily braced internally. Focal believes the MDF material has inherent advantages for loudspeaker construction, including stability and resistance to vibration. The front baffle contains Focal’s MRRs around the drivers for increased strength. Additional items inside the Stella include: additional acoustic wadding for bass control; precision, 20%-thicker internal wiring to limit current losses; and premium crossover components.

The Stella Utopia’s base is a thick laminar material with permanent, low-profile, integrated wheels on the bottom and four threaded holes in the corners to accept Focal’s three-piece (threaded screw, upper cone, and lower cone), custom, decoupling spike assembly, in addition to a magnetically attracted counter-spike (spike cup) to protect tile and wood floors. On the rear of the Stella’s base is a DC power connection for the EM woofer’s external power supply. There are WBT bi-wire/bi-amp speaker connections for the main (midrange and tweeter) and bass (woofer) speaker sections. (Focal supplies custom metal jumpers for single-wired use, when you’re not bi-wiring or bi-amping the speakers.) The upper-front portion of the Stella’s base is a wide, flared outlet for the bass module’s reflex port. This port is said to add no distortion or noise from air flow, as well as no dynamic compression of the woofer, which is integrated directly above the speaker’s base. (The woofer module has an opening on the bottom that mates with the shaped, front-ported outlet of the speaker’s base.)

The 13″ EM woofer occupies the upper front of the bass module. The EM woofer’s cone is made of the same third-generation “W” composite material described in the midrange module section below but optimized for the bass-frequency range. Unlike most drivers available today using permanent magnets made from various materials, Focal has chosen an electromagnet. This is a metal core formed into a magnet by an external power source used to pass electric current through the field-coil surrounding the core. This design choice allows Focal to maintain an optimal balance of efficiency and low-frequency output extension. The EM woofer is circular in diameter (clearly visible with the grille cover removed). With the grille cover on, the woofer seems to have a vertical oval shape, which adds to the svelte slender look of the Stella—a nice design touch.

The two midrange modules (directly above the woofer module at the top of the speaker) look identical. The 6.5″ midrange is centered in the module, in line with the tweeter and woofer. The cone is made of Focal’s third-generation “W” composite material: selective fine-weaved, long-strand, glass-fiber tissue above and below a driver-specific-thick, structured, resin-foam core. The motor system consists of Focal’s Power Flower motor (a series of double-stacked ferrite rings in a circular array surrounding the voice coil) that supports greater magnetic energy and vented cooling of the voice coil that is proportional to the amount of movement during operation: the more cone movement, the more venting and thus the more cooling. The midrange also contains Focal’s mechanical Neutral Inductance Circuit (NIC). This NIC Faraday ring is used to optimize the magnetic field around the voice coil, increasing performance by delivering greater clarity, dynamics, and definition. Finally, the midrange driver has the Tuned Mass Damper (TMD), born from the use of finite element analysis to selectively tune the driver’s surround suspension and eliminate unwanted resonances, resulting in more linear cone movement, especially in the 1kHz-to-4kHz range.

The tweeter module, sandwiched between the two midrange modules, contains the inverted, pure beryllium dome tweeter, vertically in line with the other drivers. Unlike the removable cloth grille covers of the other drivers, the 1″ tweeter has a permanent metal grille cover protecting the tweeter. The driver’s operational bandwidth is 1kHz to 40kHz. The Infinite Acoustic Loading (IAL2) of the tweeter has a low resonance frequency that is nearly two full octaves below the in-system crossover frequency of 2.2kHz.

Unlike some of the large high-performance speakers that ship in multiple smaller cases, the Stellas come fully assembled. That’s the upside. The downside is that a forklift is required for delivery. Each fully assembled Stella speaker is shipped in a very large wooden crate weighing nearly 600 pounds. The crate is provisioned for forklift movement along the long side of the structure. The courier delivered the crates to my garage via forklift, where they sat for a couple of days until the piano movers could remove the speakers from the crates and bring them into my listening room. The Stella lays flat on its back in the crate during shipping and is protected on all sides internally with very strong closed-cell foam supports cut precisely for the speaker’s outlines. The piano movers set the crates vertically as directed in the unpacking instructions and rolled each speaker out of its crate. The 374-pound Stella had protective padding around the lower base and a cloth “robe” covering the entire speaker. Once the movers got the speakers into the house, we rolled them into initial positions and installed the three-piece decoupling spikes and counter-spike cups. The next steps were to remove the “robe” and padding on the base to reveal a beautiful Ash Grey-colored speaker. Final steps involved unpacking the EM-woofer power supply for each speaker and making the AC-inlet connection, followed by the EM-power-supply-to-EM woofer DC power connection. I wired up the speaker terminals in a bi-wire configuration and turned the EM power supply on by pushing the power button on its top. The Stellas were ready to play music.

Before I say more about setup, it is worth mentioning that purchasers of the Stella Utopia EM Evo will most likely have all these steps of delivery and setup performed by their dealer or representative. If the owner is curious about the steps in setup, the Stella unpacking guide and user manual has useful basic instructions for getting the speakers set up and playing satisfactorily. Some of the information includes advising how placement in the room affects bass, suggested locations to use and avoid, how to connect the speakers and EM module, how to install decoupling spikes, how to set listening distance and speaker separation, and how to troubleshoot set-up issues. Lastly, there is a section devoted to the use of the OPC+ filter settings and the EM woofer power-supply level.

Once the Stellas were initially set up with nominal settings, physically moved and adjusted for best in-room sound, and playing music for several weeks, I began to listen more critically and explore the OPC+ and EM woofer adjustments.

One of the unique features of the Stella Utopia EM Evo is the combination of OPC+ filtering and EM-woofer-power-supply sound-personalization adjustments. The EM woofer power supply has three settings for bass output that can be selected based on the amplifier used, personal preference, and/or the speaker’s room interaction. The OPC+ filter (hidden behind a trap door on the rear panel of the lower midrange module) has four frequency band adjustments (bass quality, midrange, tweeter slope, and tweeter level), allowing three settings for each. All OPC+ filter bands and the EM woofer control contain a nominal setting followed by a level adjustment that allows for a setting above and below normal. Together, the sum total of settings available on Stella adds up to a healthy 243 combinations!

Starting with the EM woofer level-control, the “2” setting adds more output compared to the “NOM” setting. This additional output starts slowly in the lower bass frequencies and rises as frequencies increase until it reaches about +2dB at 150Hz, then begins to decline to flat when it gets to the woofer crossover frequency of 230Hz. In this setting, the upper bass is more pronounced and can, in some instances, serve to counter a room anomaly or a floor-bounce issue in that frequency range. If the user wants a fuller upper-bass sound than what is available in the “NOM” position, this setting will also do that. The ”1” setting is used to lower the bass output from 230Hz on down to the lower bass frequencies. This setting drops the output by about 1dB and is pretty linear in function across its range of operation. In this case, the setting can be used to simply reduce the bass output of the EM woofer. Subjectively, this setting provides very tight and linear bass with even more control than the already excellent “NOM” setting.

The Bass Quality adjustment in the OPC+ filter adjusts the bass frequencies from approximately 50Hz to 100Hz centered around 70Hz. Position “3” adds 1dB while position “1” drops the output by 1dB. Position “2” is nominal. The Midrange adjustment in the OPC+ filter operates linearly from 230Hz to 2.2kHz. Position “3” adds 1dB while position “1” drops the output by 1dB. Position “2” is nominal. Like the midrange, the Tweeter Level adjustment in the OPC+ filter operates linearly just above its start frequency of 2.2kHz to well past human hearing. Position “3” adds 1dB, while position “1” drops the output by 1dB. Position “2” is nominal. The Tweeter Slope adjustment operates around the transition frequency of the tweeter, 2.2kHz. This adjustment is normal in position “2,” produces a slight dip in position “1,” and adds a slight peak in position “3.” All the adjustable dB-levels listed above are approximate values. (The OPC+ and EM woofer level controls and their suggested settings under certain use conditions are listed in the user manual for further explanation.)

Using the Stella with normal settings would be just fine if that were the only option available. My main interest for most visiting speakers is the bass performance in my listening room. The Stella performs very well with those default settings. However, given that I had the opportunity to further refine the bass, I took advantage of the situation and opted for the subjectively tighter, slightly more linear, and controlled bass of the EM woofer power supply’s “1” setting, even though the output was reduced by about 1dB. The reduced bass output was not a large concern; I ended up turning the OPC+ midrange and treble controls down to compensate and bring things back into subjective balance.

I listened to the Stellas with the speaker grilles on and off. There is a difference. Anytime you put something between you and the speaker’s driver, it is highly probable that a difference will be noticed. How much of a difference may depend on the listener and his/her taste. It will certainly depend on whether the manufacturer/designer designed the speakers to be used with or without grilles, which I do not know. In the case of Stella, the difference between grilles and no grilles came down to a slight reduction in transparency. After the comparison and settled listening, I gather one could easily adjust to the change if grilles-on are the preferred visual appearance.

Once properly set up and adjusted for the listening environment, the Stella Utopia EM Evo proved to be an excellent sounding speaker. There was an uncanny amount of transparency, reminiscent of my time with some electrostatic loudspeakers. Unlike most ESLs, the Stella has frequency extremes to balance the sound and bring things into a more holistically complete perspective. Like an ESL, there is that feeling you are hearing more of what is on the recording in the critical midrange. With the Stella, one tends to hear things going on in the background during the performance more clearly. Things like a delicate hand movement on a subtle guitar vibrato by Kenny Burrell on “Mule” from Midnight Blue (Qobuz 24/192), Stanley Turrentine’s slightly muted coughing around 3:27 into the same song, or the small sound of a key movement by Art Pepper during a performance of “You’d Be So Nice to Come Home To” (Tidal 16/44.1).

Another feature of the Stella is the ability to keep up with the rhythm and pacing of music. On Herbie Hancock’s “Rockit” from the Future Shock album, the lightning-fast rhythm of the constant synth percussion (and the plethora of electronic instruments overlayed in and out of the mix) was rendered with such speed and precision that the entire composition took on an exhilarating sense of energy—an upbeatness that accelerated the enjoyment of this early 90s tune. Friday Night In San Francisco proved to be another treat. The rapid-fire playing of guitar from Paco de Lucia, Al Di Meola, and John McLaughlin was as enjoyable as always, but there was an additional amount of clarity delivered by the Stella’s ability to parse, separate, and easily portray these individuals and yet keep their performances holistically complete. I’ve always considered this live performance an interesting contrast to their studio album Passion, Grace & Fire. In the live album it has always seemed as if they are stepping on each other at times during the performance. With the Stella, it still sounds that way, but the added clarity reveals their individual playing more clearly during those instances.

Making a multi-driver speaker play as a single entity is not an easy task. The Stella pulls the feat off well. One way to identify this trait is to play a single instrument over one speaker channel. Another way is to play multiple instruments in one speaker and observe how well the speaker pulls their imaging off. On Art Pepper’s “You’d Be So Nice to Come Home To,” the arrangement puts Red Garland on piano, bassist Paul Chambers, and drummer Philly Joe Jones in the same right channel. This trio of performers exercise all the drivers in the speaker’s array while simultaneously requiring a single speaker to keep each instrument sounding real yet separate from the other instruments. The Stella accomplishes this feat perfectly with great separation of the three instruments; yet all are complete sounding during playback, regardless of differences in dynamic contrasts at any given moment.

Bass performance is tight, controlled, and realistic sounding. Brian Bromberg’s performance of the classic Beatles song “Come Together” (Qobuz) is an excellent example. The bass is present and rich, yet quick as Bromberg slaps the fretboard to stop a string tone. Each individual note sounds true and realistic. Moving to something a bit more synthetic, James Blake’s “Limit to Your Love” (Qobuz) produces a pulsing bassline that quickly stops at its end and yet is superbly controlled during rapid note pulses. Stella plays these synth bass notes with ease, while producing the low-frequency power in this track.

Voices are rendered with precision played back through the Stella. Ella Fitzgerald’s super-pure voice during the Verve years is unmistakably lovely and captivating. Yet, when we listen to her singing during the Pablo years, we hear Ella’s magnificent voice aged like fine wine through these speakers. Male vocals cast a similar spell with some of the greats. Take Nat King Cole singing “Welcome to The Club.” His voice is as pure as ever when backed by a big band playing with vigor and rhythm. Name your favorite vocalist and then listen to them through the Stellas using excellent sources and electronics. You will most likely be more than pleased with the results.

Soundstaging and imaging from the Stella speakers is excellent in terms of instrument placement laterally across the stage, and image height is very satisfactory for a large speaker. Playing anything with embedded processing, like Q-Sound recordings, easily move sounds around the listener, far outside the speaker boundaries and behind your head if processed to be placed in those locations—think Roger Waters’ Amused to Death (Qobuz, Tidal, LP, CD). Standard recordings give well-placed arrangements based on the mixing engineer’s selections, while more minimalist stereo-mic recordings depict a realistic space with room ambience when captured.

I can’t identify any glaring weakness or issue with the Stella Utopia EM Evo that can’t be ameliorated with proper set-up adjustments, supporting components, cables, and/or sources. Subjectively, in my listening space, with such a large and bass-friendly room, I’d like to have had a few dB more bass output, keeping the same performance achieved with the bass settings staying exactly where I’ve preferred them. This is probably a solution the larger Grande Utopia EM Evo would provide. The other item I noticed is that such a large speaker can slightly signal its location at times when instruments are hard panned directly to the speaker. I should note that if I move my listening position another three or more feet away, this is much less noticeable. Given that most large speakers have this issue, it shouldn’t be much of a concern. Lastly, I’d prefer just a tad bit more lower-midrange warmth without it affecting the rest of the midrange frequencies. This mostly falls into the supporting components and cables category. With that noted, I’ll say that when I play an emotional piece of music like Bill Withers’ 1973 Live at Carnegie Hall rendition of “I Can’t Write Left-Handed,” and the more modern 2010 version sung by John Legend and The Roots on their album titled Wake Up!, these minor quibbles quickly dissolve away, as I slide into the enormously poignant and heartfelt renditions of the Withers song.

The Stella Utopia EM Evo acquitted itself well during the evaluation period, with impressive transparency, lightning quick transient response, near unlimited dynamic playback capability, excellent lateral soundstaging and imaging, very good image height, and great instrumental separation to complement very tight, controlled, and refined bass response. The Ash Grey finish on the evaluation pair is as beautiful to look at as the sound produced by the speaker. Since the current version Stella’s introduction in 2018, many new upper-high-end speakers have entered the market from several manufacturers. Today, these Stella Utopia EM Evos continue to produce excellent sound that is competitive with all of them. Go listen and hear for yourself how Stella(r) sounding they can be.

Specs & Pricing

Type: 3-way dynamic loudspeaker
Tweeter: 1″ IAL2 pure beryllium inverted dome tweeter
Midrange: 2x 6.5″ “W” composite sandwich technology midrange
Woofer: 13″ “W” composite sandwich technology woofer
Impedance: 8 ohms nominal (2.8 ohms minimum)
Crossover frequencies: 230Hz, 2200Hz
Frequency response: 22Hz–40kHz (±3dB), 18Hz (-6dB)
Sensitivity: 94dB (2.83V @ 1 meter)
Recommended amplifier power: 50–1000 watts
Dimensions: 21.75″ x 61″ x 32.69″
Weight: approx. 374 lbs. ea.
Finish: Carrara White, Black Lacquer, or Ash Grey
Price: $149,998 pair

FOCAL NAIM AMERICA (Distributor: U.S. & Canada)
313 Rue Marion
Repentigny, QC J5Z 4W8, Canada
(866) 271-5689 (Canada)
(800) 663-9352 (U.S.)
focalnaimamerica.com

Reference System
Analog tape: Otari MTR-10 Studio Mastering (¼” 2-track) tape deck with custom Flux Magnetic Mastering Series repro head and secondary custom tube output stage, Studer A820 Studio Mastering (¼” 2-track) tape deck (x2), Studer A80VU MKII Studio Mastering (¼” 2-track) tape deck, ReVox A700 (1/4″ 2-track and ¼” 4-track heads) tape deck, Stellavox SP7 (¼” 2-track) tape deck with ABR large reel adapter, Nagra IV-S tape deck with custom large reel adapter, ReVox G-36 (¼” 4-track) tape deck
Analog vinyl: Basis Audio Debut Vacuum with Synchro-Wave Power Supply, Basis Audio 2800 Vacuum ‘tables; Basis Audio SuperArm 9, Basis Audio Vector IV (x2), Graham Phantom III tonearms; Lyra Atlas, Lyra Atlas SL, Lyra Etna, Lyra Etna SL, Lyra Titan-i, van den Hul Colibri XGP, Hana SL, Hana Umami Red, Hana Umami Blue, Ortofon Verismo cartridges
Analog phonostage: The Raptor (Custom), Ayre P-5xe, Musical Surroundings Phonomena II+ w/Linear Power Supply, Zanden Model 1200 Signature
Digital source: Intel i7 10th generation processor-based music server hosting JRiver Media Center, Roon, Qobuz, and Tidal. Currently researching reference DACs
Preamplification: Dual Placette Audio Active linestage
Amplification: Custom/Modified solid-state monoblocks
Loudspeakers: Vandersteen Model 3a Signature with dual 2Wq subwoofers and dual SUB THREE subwoofers using M5-HPB high-pass filter, Focal Stella Utopia EM EVO
Cables: Assortment of AudioQuest, Shunyata, Tara Labs, Acoustic Research, Cardas, and custom cables
Support: Minus-K BM-1, Neuance shelf, Maple wood shelf, Symposium Ultra
Acoustics: Walker Audio
Accessories: Aurios Pro, Pneuance Audio, Walker Audio, Klaudio KD-CLN-LP200, Kirmuss Audio KA-RC-1, VPI 16.5, Clearaudio Double Matrix Professional Sonic
Room: 18′ (W), 8′ (H), 43′ (L)