Acelec Model One loudspeaker

The Acelec Model One speakers I’m auditioning ($6495/pair) are not princesses in pink, or frog green, or made of some chemically distilled polypudding. Nor are they conventional-beyond-reason MDF boxes covered with stick-on vinyl pretending to be wood. The Model Ones are squat, small, serious-looking, two-way standmounts. They are 11.2″ tall, 7.7″ wide, 11.5″ deep, and 37.5lb heavy.

My review samples look serious because they are constructed of black, 15mm-thick, internally damped “bituminized aluminum” panels, which, besides being rigid, look full-metal stealth and recording-studio professional. Cees Ruijtenberg of Sonnet Digital Audio—Acelec is a Sonnet Digital Audio brand and Cees is Acelec’s chief designer—wrote to me in an email that this well-damped stiffness “avoids ringing and time-smearing with regard to fast, powerful transients.” If you don’t want black, you can also get silver, and fancier colors available on request.

Ruijtenberg continued: “We believe that our aluminum construction differs from what we see from other manufacturers. Typically, their panels are tightly connected to each other, or their cabinet is milled from a single piece of aluminum. These tight connections … make their enclosures resonate like a bell. In our design, the panels are connected with a kind of rubber glue so that there is no unity between the individual panels.”

The Model One’s Mundorf AMT tweeter and 5.9″ sliced-paper–cone Scan-Speak bass/mid driver, which has a neodymium magnet, are crossed over at 1.8kHz in what Cees calls a “dual slope design”: “The crossover frequency is initiated with a first-order [filter], 6dB/octave, but further away on either side of both slopes, a second-order [filter]—12dB/octave—kicks in. This allows for a milder phase behavior at the crossover frequency.”

I asked for placement tips. “Placement within a normal living environment was also a design goal so that performance would not be hampered, for example, by close proximity to room boundaries (e.g., walls and corners),” Ruijtenberg wrote. “Furthermore, the design had to behave efficiently and act as a simple load for a wide range of amplifiers, encompassing delicate tubes as well as powerful solid state types.” Reading this caused me to pause and applaud. I mean, is it really that difficult or a compromise to make a speaker easy to position and easy to drive?

Setup

More than any speaker I’ve used before them, the Acelec Model Ones looked and felt like they were made especially for my heavy, 24″ Sound Anchor Reference stands. Their gray-black surfaces matched tone- and color-wise, and the One’s 12″ × 8″ footprint exactly matched the Sound Anchor’s 12″ × 8″ platform. Their textures and densities matched well too. Speaker and stand seemed to join visually and physically.

I mated the Model One speakers to my stands three different ways: first, with only gravity and friction holding the Acelec’s textured bottoms to the Sound Anchor’s textured tops. They sounded crisp and lively like that. Next, with pea-sized balls of Blu Tack between the Ones and the stands, I discovered a silent atmospheric transparency that I found appealing. Finally, with the Model Ones sitting on the supplied 1″-high aluminum cones, their boxes seemed to disappear more than they did sitting loose or puttied to the Sound Anchors.

Acelec’s screw-on cones placed the tweeter’s centers about 33″ from the floor, approximately 1″ below the center of my ears in my listening position. I did all the listening described in this review with four cones under each speaker.

Consistent with the design brief, Acelec’s Model Ones were not fussy about placement. I moved them around in a deliberate attempt to find where they didn’t work. I ended up with about 30″ from their front faces to the wall behind them, 74″ apart, and 96″ from my ears. This was the position in which they had the clearest, strongest voice.

The Acelec Model Ones are made in the Netherlands, imported and distributed in the US by Audio Art Cable. Rob Fritz, proprietor of Audio Art Cable, suggested I try his own AAC Statement e SC speaker cables ($1220/4′ pair). I told him I would, but only if he felt certain it would give me the best chance of hearing everything the Model Ones had to offer.

I also tried the Acelecs with my reference Cardas Clear Beyond cables ($9220/2m pair). To my ears, the Cardas let the Model Ones sound more corporeal and more fully detailed than the Audio Art cables did. I also tried the silver-wire Kangai-level cables from Ikigai Audio ($6500/2m pair), which I thought rocked the One’s dynamics and purity levels up a full notch. In the end, I used the Audio Art wires because they were a good match. They played all genres of music in an engaging fashion, made exceptionally detailed bass, and did not appear to compromise the Acelec’s uncanny transparency.

Listening

During my first day of break-in listening, the most interesting thing I noticed was how much more intelligible singer/guitarist Bo Carter’s lyrics were—how his words were better formed and enunciated and how much more obvious and erotic his double entendre seemed. Playing the Yazoo Records’ Bo Carter anthology Twist It Babe (1931–1940) (16/44.1 FLAC, Yazoo/Tidal), the Model Ones presented the artist’s voice singing campy songs with a starker, more microscopically rendered clarity than the Klipsch RP-600M IIs that preceded them in my loudspeaker auditioning queue. With the budget-level Klipsches, Bo’s voice seemed to emerge from an attractive but slightly hazy neon-lit environ. With the Acelecs, the sound was stark, dark, and no-glass clear.

No matter how hard audio designers try, every audio product seems to end up sounding like what it’s made of. Plywood boxes sound like plywood boxes, with ring tones of varying duration, depending on the size of their cabinet. The ubiquitous MDF cabinet contributes a dead-thunk box-speaker sound.

Today, in order to minimize such cabinet-caused colorations, a small cadre of widely respected, top-level speaker manufacturers make cabinets out of aluminum. The engineering benefits of aluminum are obvious and seductive, specifically its high stiffness-to-weight ratio. But does aluminum really disappear as well as its proponents claim?

At audio shows and people’s houses, I’ve auditioned a variety of YG Acoustics speakers, which use milled aluminum panels, and Magico speakers, which use extruded aluminum panels and other forms, and I thought both speaker brands shared a distinct and appealing form of clarity not found in speakers using more sundry cabinet materials. I can also report what I experienced reviewing two other brands of loudspeakers using aluminum cabinets: Genelec’s G Three, which uses a biomorphically shaped cast aluminum cabinet, and Stenheim’s floorstanding Alumine Three, which uses CNC-machined aluminum panels that vary in thickness from 0.5″ to 1.0″.

The Genelec G Threes demonstrate that aluminum speaker cabinets can come close to disappearing. When I compare them (by memory) to the thicker, taller aluminum cabinets of Stenheim’s Alumine Threes and now, directly, to Acelec’s Model Ones, I can hear the thin-walled G Threes as having a faint, high-pitched metallic taint lacing their grainless, reference-level transparency. If memory serves me, the ringtones of Stenheim’s tall cabinets were nearly impossible to find; if they were there, they merged inconspicuously with whatever low-frequency sounds the ports and bass drivers were emitting.

The Acelec Model One’s aluminum panels came even closer to complete silence. Nevertheless, when I tried to find it, I noticed what I presumed was the specter of its aluminum enclosure: a slight, eerie density hovering near the musical program. Its level was exceedingly low, so I did not regard it as a coloration. I thought the fact that I could notice it at all was proof of how extraordinarily clear, microresolved, and uncolored the Acelec Model Ones are.

After transparency, the One’s most conspicuous trait was its unflappable ability to deliver perfectly sorted, minutely organized, naturally displayed recorded data. In this performance category, it equaled TAD’s $32,250/pair CE1TX monitors, which I thought sorted and displayed recordings more completely and effectively than any speaker I had previously encountered.

NEXT: Page 2 »