Sonus faber Duetto Powered Wireless Speaker Review

Sonus faber Duetto Introduction

After writing a preview article about the new Sonus faber Duetto wireless active stereo speakers ($3,999/pair), I was excited to be among the first reviewers in the United States to give them a thorough evaluation. These attractive stand-mounts are part of a growing category of active speakers that have DACs, streaming functionality, and input switching built in — all you need is a phone or tablet and an account with a streaming service or two, and you have a whole HiFi system. The Duetto speakers accommodate Apple AirPlay 2, Chromecast, Spotify Connect, and Tidal Connect, via WiFi or ethernet. They’re also Roon Ready. Bluetooth is available for convenience, though sonic performance will be limited compared to network sources. Physical connections include HDMI eARC, optical Toslink, and a pair of RCAs that can be configured for phono or aux. A subwoofer output rounds out the hidden connectivity panel beneath the primary loudspeaker, which can be set as either the left or right speaker.

Sonus faber Duetto Design Details

As you would expect from Sonus faber, the Duetto is a great-looking speaker. Everyone who laid eyes on them (including both my girlfriend and her mom) appreciated their lute-shape cabinets, clean front baffles, graceful proportions, and walnut wood veneer finish. They even look cool from behind, thanks to the ribbed, die-cast aluminum heatsink that houses the speaker’s port and provides passive cooling for the internal electronics. The secondary speaker has a Sonus faber logo embossed into its leather top, but the primary speaker’s top panel features the company’s slick-looking illuminated Senso touch interface embedded into the leather. (I’m not sure if this is genuine leather or a vegan alternative. If I had to guess, I’d guess the latter, but it looks and feels nice.) The Senso interface is designed to allow the user to switch inputs and adjust volume with the swipe of a finger. The horizontal status bar toward the front of the top panel changes color to indicate which input is active, and since the speakers have no display, this proved to be a useful feature.

My Duetto preview article describes the speakers’ design, features, and functionality in detail, but I will repeat the salient facts here. The Duetto is a two-way ported design, and its front baffle proudly shows off the 0.7-inch soft dome tweeter and 5.25-inch mid-woofer — unless you choose to cover them with the included magnetic grilles. These aren’t off-the-shelf drivers; they’re custom-designed from scratch by the Sonus faber R&D team in Vicenza, Italy. Sonus faber tells us that the silk dome tweeter is equipped with a ferrite magnet system and a copper cap to “amplify the driver’s emphasis on the lower frequencies while keeping the highest notes smooth and clear.” The tweeter also sits within an integrated waveguide that reportedly increases off-axis response and “guarantees an astonishing listening experience from every part of the room.”

The paper pulp mid-woofer features a neodymium magnet and Sonus faber’s new Organic Basket, which aims to prevent resonance and ease the air-flow production by the long-excursion of the driver. The mid-woofer also features a copper cap and aluminum ring, and is powered by a 250-watt Class D amplifier that provides “the power needed from the mid-woofer to deliver deep and firm bass.” Meanwhile, the tweeter is powered by a 100-watt Class AB amplifier that promises accurate and smooth high-frequency reproduction. The system uses high-performance DAC chips  — an ESS Sabre DAC for the main speakers and an AKM DAC for the subwoofer output. The wireless link between the two speakers is made using UWB (Ultra Wide Band) technology, which reportedly avoids both latency and potential interference in the connection. To my knowledge, the Duetto is the first wireless streaming Hi-Fi speaker system to use UWB tech for the all-important inter-speaker connection. Sonus faber says the UWB connection guarantees a very wide frequency spectrum to send data signals at high speed.

Sonus faber Duetto: Unboxing and Setup

The speakers arrived double-boxed, which is always nice to see, particularly on products that are likely to be sold online through dealers like Audio Advice or Crutchfield. The FedEx journey from North Carolina to my girlfriend’s place in Seattle is about as long as it gets within the USA, and the speakers were no worse for wear. Inside the interior box, each speaker was wrapped in a soft cloth sack and secured in place by thick, custom-cut foam. My review sample came with a Quick Start guide, but no proper user manual. Luckily, a quick web search yielded a PDF user manual on Sonus faber’s website. Physical connections were easy enough. Each speaker plugged into a power outlet, and the primary speaker received an HDMI cable coming from our TV’s HDMI eARC jack. I also used a Toslink cable from Blue Jeans Cable to connect a Wiim Mini streamer to the Duetto’s optical input — more on that later.

Next I had to connect the speakers to WiFi and pair the primary speaker to the secondary speaker. The pairing process was simple enough, but it took multiple attempts over a period of a day and half to get the speakers connected to WiFi. After two factory resets, I was up and running. (My difficulty with this stage of the process probably came down to the fact that my review samples had previously been connected to a different network when the folks at Audio Advice checked them out before sending them on to me.)

The purpose-built Duetto stands ($749/pair, sold separately) were not yet available when I began my review in early November of 2023, so I placed the Duettos on a pair of 26-inch steel VTI speaker stands filled with sand. I normally use small globs of Blu Tack to adhere speakers to these stands, partially because the putty provides a tiny amount of vibration isolation, but mostly because it usually secures speakers well enough that I don’t have to worry about their shifting around on the stands, or worse — falling off entirely. But the bottoms of the Duetto speakers are covered in a layer of soft padding, presumably designed to provide some isolation and scratch protection if the speakers are to be placed on a piece of furniture. The Blu Tack would not stick to this padding, so the speakers never truly felt secure on my stands. For this reason alone, I’d be inclined to spring for the dedicated stands, which can be bolted directly to the bottom of the Duettos. The dedicated stands also offer cable management, which would have been most welcome on the primary speaker in particular, as it never had fewer than three cables spewing forth from the hidden panel around back.  

I auditioned the speakers during an extended visit to Seattle, and I’ll be the first to admit that my girlfriend’s living room is not an acoustically ideal environment. It’s not treated, and it is partially open to the kitchen. Furthermore, the layout of the living room and the location of the front door demand that any audio system be scooted over a bit to one side, so the right speaker is closer to an adjacent side wall than the left speaker is. But I think most folks who buy all-in-one active streaming speakers like the Duettos are not going to place them in dedicated listening rooms with professional acoustical treatment and a single listening chair. These speakers are destined for living rooms, bedrooms, and offices — real-world spaces with real-world compromises. And I’ve logged thousands of hours of listening in this particular room, so I felt confident in conducting the review in this space. I had plenty of time to experiment with speaker placement during the month that I spent with the Duettos. The manual recommends setting up the speakers in an equilateral triangle vis-à-vis the listening position, but I achieved the best results with an isosceles approach, in which the tweeters were 100 inches apart from each other, and 131 inches away from my nose. The backs of the speaker cabinets ended up 29 inches out from the wall behind them (I refer to the wall behind the speakers as the “front wall” because it is in front of the listening position, but not all reviewers adhere to this same logic). The manual recommended a bit less distance between the speakers and the front wall, but any such placement resulted in too much bass reinforcement. These speakers can produce a superabundance of bass if not set up carefully. The left speaker was 26 inches away from the left wall, but the layout restrictions I referred to earlier meant that the daylight between the right speaker and right wall was limited to 13 inches. I started with the speakers toed in to the listening position so that they were essentially pointed at my ears, but the top end was a bit too hot in this orientation. These are not the soft and forgiving Sonus fabers of yesteryear. I ended up with the speakers pointed almost straight ahead, with just a few degrees of toe-in. This setup resulted in a somewhat narrow sweet-spot, but the soundstage was focused and the tonality more in balance.

Sonus faber Duetto: In Use

Before I get into my listening impressions, I need to explain that my review samples of the Sonus faber Duetto were in fact pre-production samples, not the final production versions that customers will receive. I was not made aware of this fact until after I had agreed to write the review and had begun my testing. The firmware running on the speakers had not been finalized, and the all-important Sonus faber mobile app, which will be used for setup and operation of the speakers, was not yet available for iOS or Android. (it was still not available as I wrote this in late December of 2023.) This put me in a bit of an awkward position as a reviewer. In evaluating a product like the Sonus faber Duetto, you’re mainly commenting on three things. First, the physical objects that you take out of the box — the industrial design, the build quality, the materials, the fit-n-finish. Next comes the sound quality and the engineering behind it. And finally, you’re reviewing the user experience. That includes the app used for streaming, control, and settings, and the software running on the speakers themselves. Does the app crash? Does the remote control work? Do the speakers behave as you’d expect them to? These usability factors have a big impact on the day-to-day pleasures and/or frustrations that come from using a product of this type over a period of time.

Operational Issues with our Review Units

It will come as no surprise to Sonus faber fans that the build quality and fit-n-finish of the Duettos were both very good. Not on the same stratospheric level as the brand’s uber-expensive, hand-made-in-Italy speakers, but certainly on par with comparable products from other high-end brands. No complaints there. And as I will discuss in detail — spoiler alert — the speakers sound damn good, too. But my time with the Duettos was riddled with enough snags, quirks, and annoyances, that it became clear to me — immediately — that the product was still half-baked, at least on the software side of things. Which leads me to the awkward position I referred to earlier. I don’t want to dwell on operational hiccups that might very well be resolved by the time you get these speakers home, should you choose to buy them in 2024 or beyond. I think doing so would be unfair to the manufacturer. But at the same time, I can’t simply gloss over the many usability issues that I encountered, based on the assumption that they’ll go away. Doing so would be unfair to our readers and to potential buyers doing their due diligence by reading reviews before making a purchasing decision. Of course, there is one very simple solution to this situation: manufacturers shouldn’t send out incomplete products for review. And reviewers can help by declining to review prototypes until they’re truly ready for prime time (assuming we’re told in advance).

So while I don’t want to dwell on the problems that I ran into with the Duettos, I will list them. The owner’s manual describes a startup chime that should sound when the speakers are turned on, but whenever I turned them on, I heard only a few disconcerting crackles and pops. The remote control would not work at all when the speaker grilles were on, so I left them off for all of my listening. Even with the grilles off, I had to point the remote directly at the primary speaker and press the buttons quite hard. Still, the speakers only responded to the remote some of the time. When I used the remote to turn on the speakers, they wouldn’t fully turn on until I touched the status bar on top of the primary speaker. So I tried to ditch the remote and use the touch controls instead, but these rarely worked either. For example, when I tried to cycle through the inputs using the touch controls, only about 20 percent of my finger-swipes actually registered. Most of the time, the speaker just didn’t respond. I expect that buyers will be able to select their desired input using the mobile app, but the temporary web-based app that I was able to use didn’t control input selection. Although I tried to disable the speakers’ auto-off function using the web app, they would turn themselves off any time they didn’t receive a signal for a short period. Twice, they turned themselves off while I was listening to music. If the HDMI-connected TV was on when the speakers turned themselves off, the TV turned off as well. But if the TV was off when the speakers turned themselves off, then the TV turned on. Sometimes, the speakers turned the TV on for no apparent reason; I’d wake up in the morning or come home from running errands to find that the TV had been turned on. The Duettos occasionally changed inputs of their own accord as well. Once, the speakers spontaneously ramped up the volume while I was listening to music. And the first time I tried using Spotify Connect, the speakers played at full volume without warning. It was so loud and so sudden that I literally leapt into the air. That easily could have damaged the speakers — or my ears. When I first tried to use the HDMI eARC function, the speakers emitted a deafeningly loud robotic cacophony, as if R2D2 were being tortured to death. (I later discovered via trial and error that I needed to adjust the settings on my Sony A80J TV, selecting not only the stereo PCM audio output setting, but also the “Auto” setting under the HDMI eARC options.) Finally, if I stood between the speakers while music was playing, the secondary speaker would start emitting a fuzzy-sounding static. I expect that these problems will be resolved by future firmware updates, and that the final production version of the Duettos will deliver a smooth user experience.

Although the mobile app was not available, I was able to use the web app, which offered a few useful features. There was a High Frequency control that allowed the treble gain to be adjusted from -2dB to +2dB. Sonus faber says it’s a 2nd order high shelving filter at 5kHz. There was a left-right balance control, and an option to select whether the speakers were positioned near a wall or in free space. I could also indicate in the app whether the primary speaker was in the left or right position. This was much more convenient than using the physical button located on the primary speaker’s hidden connection board. Finally, there was a defeatable “Loudness Maximizer.” When engaged, this implements a Fletcher-Munson curve correction to boost the low frequencies and the high frequencies when the speakers’ volume is set below 30 percent. Like the “Loudness” switches common on older amps, the Loudness Maximizer is designed to compensate for the fact that the human ear is less sensitive to the frequency extremes at lower volumes. Unfortunately, the web app did not include a volume control, and there was no clear way to know when I had hit the 30% threshold when decreasing the volume.

Sonus faber Duetto: Listening Impressions

Despite my lengthy list of operational snafus, I had many deeply enjoyable listening sessions with the Duettos. When auditioning any piece of audio gear, I like to have a similarly-priced competitor on hand whenever possible, so that I can draw direct comparisons and provide additional context for my listening impressions. Alas, that didn’t work out this time around, so I did my best to compensate by putting in considerable hours and listening critically to a wide variety of material.

Side Note on Active Streaming Speakers:

There are many interesting options for all-in-one streaming systems at and around the Duettos’ $4K/pair price point. If I were considering the Sonus fabers, I would also check out the Cabasse Rialto ($3,995/pair), of which I caught a tantalizing glimpse at T.H.E. Show 2023. Normally, the combination of KEF’s LS50 Wireless II and tiny KC62 subwoofer costs $4,300, but at the time of writing, the combo can be had for $3,500, thanks to a limited-time sale. Denmark’s Buchardt Audio sells its Anniversary 10 active speaker bundled with the Platin Hub wireless streamer for €4,100, which is a little less than $4,500. These speakers are some of the first to use Purifi’s Ultra Long Stroke Low Distortion Woofers. You’d have to stretch your budget to $5,500 to get Dynaudio’s Focus 10 active streaming bookshelf speakers, but you’d also get the unusual benefit of built-in Dirac Live Room Correction. The JBL 4329P are larger than the other speakers mentioned here, but similarly priced at $4,500/pair. This list is hardly exhaustive, and if you’re willing to add your own streamer to a pair of active speakers, there are countless more options, including the RBH Sound 61/AX Active Monitors ($3,500/pair). 

The folks at Sonus faber told me that they’re working on incorporating Qobuz streaming into the new app, but the feature isn’t expected to be available at launch. In any case, the Sonus faber app wasn’t ready during my testing. Qobuz doesn’t yet have a Qobuz Connect feature, so the only way to get Qobuz from my iPhone to the Duettos was to use AirPlay 2, which uses lossy compression. No thanks. Chromecast is lossless, but it isn’t gapless, meaning it inserts pauses between tracks even when they’re supposed to flow smoothly from one to the next. If you’re listening to a symphony, or to an album like Sgt. Pepper or Abbey Road, that gets annoying really quickly. So my workaround for the review period was to use a Wiim Mini streamer to play lossless and hi-res music from Qobuz, and send it to the Duettos via an optical cable. Unless otherwise noted, all of the following was played in this way.

Dolly Parton’s song “Jolene” has been covered by countless artists, but my favorite version is probably from Mindy Smith’s 2004 album One Moment More (16 bit/44.1kHz). It doesn’t hurt that Dolly herself is singing harmony. On the Duettos, Mindy’s lead vocal sounded present and natural. I was almost incredulous at the amount of bass produced by those small woofers, and how easily they reproduced frequencies that would send many small 2-ways running for the hills. This wasn’t subwoofer bass, but it was certainly small floorstander bass. I did notice that the balance seemed to favor the bass and treble, leaving the midrange sounding slightly under-represented in comparison. Still, neither the highs nor the lows felt like too much on this record, and I appreciated how full the kick drum sounded.

I first discovered Mindy Smith in 2004 when she opened for Nickel Creek, whose first two albums were produced by Alison Krauss. I’ve always thought that Alison Krauss’s voice shares the clarity and expression that Dolly is known for, but Alison has smoother tone and a more subtle vibrato that suggests a certain melancholy. Her 2001 record New Favorite was mixed by 9-time Grammy-winning engineer Gary Paczosa, who has worked with Dolly many times. The heartbreaking title track, written by David Rawlings and Gillian Welch, sounds wonderful on SACD, which is how I usually listen to it. On Qobuz, it’s only available in CD-quality, but it still sounded amazing on the Duettos. The muted ostinato strum pattern and heartbeat-style bass and drums had palpable solidity, while Krauss’s voice hovered in the room like an angel, gently descending from the heavens. The center vocal image was wide and larger than life on the Duettos, which also reproduced Jerry Douglas’s lap steel guitar and dobro with faultless tone. My only criticism was that the lead vocal sounded a bit too whispery — I could hear the air escaping at the expense of some of the richness in Krauss’s voice. I also noticed that the Duetto’s volume control (both via the remote control and on the Senso touch panel) was not as fine as I would like, but that might change when the app becomes available. The take-home message is that I listened to this track over and over on the Duettos because it sounded amazing.

Continuing the sad, “breakup music” theme is Ben Folds’s 2008 album Way to Normal (16-bit/44.1kHz) which includes the song “Cologne.” The ting of the ride cymbal was notably lifelike, and that speaks to the quality of the Duettos’ tweeters. A speaker that gets cymbals just right can be irresistible to a drummer like me. The treble on the Duettos can sound forward at times, but it was in perfect balance here. There was plenty of clarity, making it easy to hear that a high-pass filter was applied to the lead vocal during the bridge but not during the verses.

 

Qobuz doesn’t have Hayley Westenra’s 2003 album Pure, which she recorded when she was just 15 years old. But the streaming service does have a 2008 compilation album called River of Dreams: The Very Best of Hayley Westenra (16-bit/44.1kHz), which includes some tracks from Pure. (Beatles fans might notice that Giles Martin played guitars and keyboards on Pure, and that Sir George Martin wrote the song “Beat of Your Heart” specifically for the record.) Some folks will think that Westenra’s music suffers from cheesy-sounding arrangements and production, and while I can’t completely disagree with that, I really don’t care. I can’t get enough of her voice, with its bell-like clarity and gentle, earnest delivery. It’s a bit like what I imagine Alison Krauss would sound like if she were a classical singer. On the song “Benedictus,” the Duettos made it easy to hear that Westenra’s voice was a little thinner and less controlled at age 15 than it is now — but still incredible. I chose this track because there is a moment (at 1:37) when cymbals crash, the bass drum thwacks, and the whole orchestra lights up, along with a choir. This is supposed to be a startling moment, but speakers lacking in dynamic range soften the musical blow too much, robbing this explosive, split-second peak of its power. The Duettos performed admirably for such a small speaker. While they don’t have as much jump factor as a big horn speaker from Tannoy or Klipsch, they brought this moment to life in a satisfying way, as long as I kept the volume at moderate levels. When I turned them up too loud, I did notice some compression, as if the sound became a little tight and hard during this section of the track.

Wanting to get a better take on the Duettos’ way with the human voice, I played the 1993 album Good Vibrations by The King’s Singers, a choral-style a cappella group with a roster that changes over time. The lineup from the early 1990s had a certain magic in its sound, and helped to cement my lifelong love of a cappella music with this record. “That Lonesome Road,” written by James Taylor, is a relatively dry recording compared to the group’s live performances in churches and concert halls. On the Duettos, I could hear the individual tone of each singer, despite the group’s supernatural blend. This is a bass-shy recording, and that’s how it sounded. There was no notion of an exaggerated low end or tipped-up top end here. The U2 song “M.L.K.” — an elegy to Martin Luther King, Jr. — was written by Bono over the pitched hum of a vacuum cleaner. So it’s fitting that the King’s Singers version, arranged by vocal music genius Bob Chilcott, uses drone-style chords, delivered with rocksteady pitch. No autotune here! Played back on the Duettos, this more reverberant mix completely enveloped me in sound. Ok, maybe I wasn’t experiencing Dolby Atmos levels of immersion, but it was definitely awesome in a surround-sound kind of way. It was during moments like this that I forgot about the Duettos’ software growing pains and just drank up the music.

One night, purely by accident, I discovered the limit of the Duettos’ impressive bass-producing prowess. Hannah came home from work and asked me to play the newly-released Taylor Swift single, “You’re Losing Me (From The Vault).” We compared the lossy version on Spotify with the 24-bit/48kHz version on Qobuz, which sounded markedly more open and detailed. The song’s incredibly deep synth bass provides the foundation for a relatively minimal electronic arrangement produced by Jack Antonoff. We listened at a loud, but still comfortable volume. Unfortunately, the sustained bass notes pushed the Duettos beyond their limit, and we began to hear some odd clicking and popping distortion, mostly in the right channel. Reducing the volume solved the problem.

I wanted to see if other bass-heavy music would trip up the Duettos’ woofers, so I turned to the rap album Volumizer (16-bit/44.1kHz) by 2 Skinnee J’s. The opening track, “Horns of Destruction,” hits plenty hard, and the Duettos handled the low-frequency onslaught with aplomb. Even when the bass guitar gets cranked up during the bridge, the Duettos were not fazed, and I’m confident in saying that these speakers can play down to 40Hz with no issues.

 

One of my favorite new artists is Monica Martin, whose 2021 single “Go Easy, Kid” (24-bit/44.1kHz) will melt your heart the first time you hear it. (Qobuz has two identical-looking versions of this song. I am referring to the version that starts with strings.) It also features full, subterranean bass that I could feel in my feet when played back at a reasonably loud level through the Duettos. The bass definitely serves a musical purpose, and didn’t distract from Martin’s voice, which sounds like a smoky single-malt Scotch whisky. This is a great bass demo track if you want to show off both depth and subtlety. The Duettos didn’t slip up here, either. In fact, at no other point during my time with the speakers did I encounter bass-related issues.

Like many of my favorite artists, Monica Martin was introduced to me by way of the monthly Watkins Family Hour shows at my favorite LA venue, Largo at the Coronet. Watkins Family Hour, composed of siblings Sean and Sara Watkins from the band Nickel Creek, has released a few albums over the years, my favorite of which is Vol. II (24-bit/44.1kHz) from 2022. Like Mindy Smith’s cover of “Jolene,” the album’s cover of Jackson Browne’s song “The Late Show” gets instant cred when you realize that Browne himself is singing backup vocals. As I listened via the Duettos, the acoustic guitar, piano, and upright bass all sounded as if they were in the room with me, lined up in front of the TV about 10 feet away. In general, the Duettos did well with smaller-scale acoustic music like this. The soundstage was expansive, and imaging was clearly defined. Texture and tone were both on point for this record as well. The resonator guitar had a crisp and suitably metallic bite, and Sara Watkins’s voice sounded natural and uncolored. The album features a number of talented guest-stars, including Fiona Apple, Lucius, Madison Cunningham, Jon Brion, Gaby Moreno, Benmont Tench, and Willie Watson.

Being a child of the ‘80s and a sucker for catchy melodies, I love The Cars. The band’s The Elektra Years box set (24-bit/192kHz) includes the 2016 remaster of the 1984 song “Drive.” Played back on the Duettos, this song’s hi-hat and tambourine sounded a little brighter than I would have liked, but the song as a whole was noticeably more three-dimensional than the CD-quality version found on The Complete Greatest Hits, and that made it more engaging to listen to. On the one hand, I sometimes wished that the Duettos had a slightly more forgiving top end. On the other hand, I appreciated that the speakers offered sufficient transparency to lay bare the sometimes subtle differences between two masterings of the same material. 

The band Fountains of Wayne was heavily influenced by The Cars. (The intro to the band’s hit song “Stacy’s Mom” was practically lifted from “Just What I Needed,” and one of the kids in the music video is even dressed like The Cars’ frontman, Ric Ocasek.) “Stacy’s Mom” is a fun song but I’ve always been obsessed with the song “Hackensack” from Fountains of Wayne’s 2003 album Welcome Interstate Managers (16-bit/44.1kHz). The song has a laid-back sound, but the Duettos emphasized the deep groove created by the shaker, kick drum, and snare backbeat. This gave the song a different perspective, and I really dug it. Despite this focus on rhythm, the Duettos reproduced the song’s rich, full-sounding vocal harmonies perfectly. The lead guitar had a reach-out-and-touch-me realism that I found intoxicating, and the lead vocal sounded textured and slightly nasal — just as it should.

Ric Ocasek wasn’t just a bandleader — he also worked as a producer for bands like Bad Religion, No Doubt, and Weezer. He produced Weezer’s self-titled 1994 album, lovingly referred to as The Blue Album by fans, which is a masterpiece of catchy tunes mixed with stadium-sized guitar slam. In CD-quality, “Say It Ain’t So” rocked hard on the Duettos, while “Holiday” focused more on Beach-Boys-style melodic lines. But the pop-rock hit “Buddy Holly” sounded bright enough to become fatiguing for me. The band’s 1996 followup album Pinkerton was made without a producer, as Weezer was going for a more raw and live sound in contrast to The Blue Album’s slick production. On the Duettos, this album was borderline unpleasant at times. The cymbals and distorted guitars on the song “Across The Sea” (16-bit/44.1kHz) sounded a bit harsh and brittle, making the song harder to enjoy, even at lower volumes. And keep in mind, I absolutely love this album. In the 1984 Honda Accord that I drove in high school, I could blast it all day via the car’s unresolving factory speakers. The same was true on the huge Sony stereo that I bought in 1994. (Sometimes, a little softening of detail can be a good thing.) If a good chunk of your favorite music features less-than-stellar production or just veers toward the aggressive side in the high frequencies, you might find that the Duettos aren’t the best match for you. They’re not as ruthlessly revealing as some speakers out there, and I am more sensitive than most when it comes to treble, so this won’t be an issue for everyone, but I still think it’s worth mentioning.

Continuing my escape to the 1990s, I listened to the 2020 remaster of the 1994 album No Need To Argue (16-bit/44.1kHz) by the Cranberries and was reminded of the first time I ever heard the song “Zombie.” I was sitting in a Ben & Jerry’s in Tel Aviv, Israel. Back then, I was entranced by singer Dolores O’Riordan’s voice — I had never heard anything like it. Listening in 2023, I couldn’t help but focus on the song’s lyrics, which desperately call attention to the senselessness of terrorism and war, and the death and destruction that they leave in their wake. Despite the heavy lyrical content, the song carried me away, and soon I was shamelessly head-banging in the living room. The tom toms had great tone, and the tambourine sounded present and natural. O’Riordan’s signature yodel-like vocal inflections sounded like a live microphone feed from the studio. This song has a hard edge, but this time there was no fatigue to contend with whatsoever. Just clarity, a satisfying tonal balance, and an appropriate amount of punch and grit when called for. The song “Ode to My Family” fared just as well, with its melodic Paul-McCartney-style bass line sounding full and easy to follow, without ever being out of balance. I had forgotten how excellent this album is, and the Duettos played a big part in rekindling the love.

Because my girlfriend is a professional baker and I’m a night owl, she often goes to bed before I do. On one such night, I took the opportunity to test out the Duettos’ Loudness Maximizer setting. I was bummed to find that Qobuz didn’t have Jupiter One’s superb self-titled album from 2007, but the service does have the band’s equally-great 2009 album Sunshower (16-bit/44.1kHz). With the Loudness Maximizer turned on and the volume set pretty low, I was impressed to find that the song “Find Me a Place” still popped out vividly from a silent background, just as it does at higher volumes. The kick drum didn’t sound anemic, as I worried it might as such hushed levels, and the high frequencies still reported for duty with surprising verve. Any speaker can play at low volumes, but not all of them still sound engaging when you have to keep your foot off the gas. I expect high-sensitivity horn speakers to pull this off, but I didn’t know if the Duettos would manage it. Perhaps the Loudness Maximizer really works wonders, but the speakers still sounded good at low volumes when I turned the feature off in the web app. Best of all, I was able to enjoy listening without waking Hannah, who was asleep just on the other side of the living room’s left wall.

Side Note: Qobuz is apparently unaware that Jupiter One, a now-defunct indie rock band from the 2000s, is not the same artist as the rapper Jupiter One, who released a bunch of music in 2023. The band’s music is jumbled together with the rapper’s, and I was definitely confused for a minute. Come on, Qobuz!

During another late-night listening session, I cued up Harry Nilsson’s 1969 album Harry (24-bit/96kHz). If you’re a Beatles fan and you don’t know Nilsson’s Beatles covers, start with his version of “Mother Nature’s Son” from this album. The delicate touch and tender tone of his vocal performance easily give Sir Paul a run for his money, and the Duettos delivered the goods. The acoustic guitar on the right edge of the soundstage had a wonderful sense of immediacy, as if guitarist Howard Roberts were sitting in the room and coming up with his part on the fly. This isn’t a fancy audiophile recording. But it is a perfect example of how even a soft song, played back at a low volume, can have just as much impact as a reference-level demo track with slam and dynamics. It’s all about evoking an emotional response, and here the Duettos were up to the task.

Toward the end of my time with the Sonus faber Duettos, I decided to take off my lossless audiophile-snob hat and test the speakers’ Spotify Connect feature, since it’s likely to get a lot of use from customers out there in the real world. I took the opportunity to listen to one of my favorite albums, Bright As You by the Americana duo Our Band. The husband and wife team of Justin Poindexter and Sasha Papernik created a staggering work with this album, and the fact that these two aren’t internationally famous is a crime. Although it’s available on Spotify (and Apple Music), the album is not on Qobuz, so it was a no-brainer for my first Spotify session on the Duettos. “Hazel” is one of the best songs on the album, with a youthful energy and an “old-school analog” sound that lets you know that this group isn’t afraid of vintage mics and tube preamps. The Duettos delivered the song with a slightly lighter and thinner tonal balance than I’m used to, but the exuberant vibe shined through nonetheless, and it occurred to me that I’d rather listen to the Spotify version on a great pair of speakers like the Duettos, than the lossless version on a lesser system. The track “Fading” is a masterclass in songwriting, from the sophisticated chord progression to the unexpected twists and turns in the melodies and harmonies. On the Duettos, the first two chords instantly established a tension between sweetness and mystery, and the phasey sound of the double-tracked vocal created a dreamy, phantasmagoric mood. The steel guitar, flutes, and vintage Mellotron sounded like they were floating down a psychedelic lazy river. Only the slightly squashed high frequencies hinted at the lossy compression being used by Spotify. The song “Out With a Girl” is the best-sounding track on the album, and the Duettos presented it with an unexpected level of clarity, despite Spotify’s low bitrates. The Duettos’ digital front end really does a great job — both the vocals and the drums were given a remarkably lifelike rendering.

Since the onset of the Covid 19 pandemic, I’ve been to fewer concerts than I’d normally attend, but I’ve seen Trousdale no fewer than three times (and I’m seeing them again in March of 2024). This country-pop-folk trio is hard to categorize but a blast to listen to. The group consists of three women in their 20s, and to my knowledge, their music is only available via streaming. That makes sense when you consider that the musicians themselves have probably never had reason to buy physical media. Qobuz has a couple of the group's older songs, but doesn’t have the 2023 album Out Of My Mind, so I went back to Spotify to blast bangers like “If I’m Honest” and “Point Your Finger.” Hannah and I cranked it up and had a little dance party. I still wish I could buy a CD or a lossless download of the album, but the Duettos reproduced the music with more detail and clarity than you might expect if, like a lot of audiophiles (myself included), you avoid lossy compression like the plague. After packing up the Duettos, we listened to the same album using Hannah’s small, inexpensive Audioengine powered speakers and Schiit Audio DAC. Together, these components cost about one tenth of the Duettos. While I’d argue that Hannah’s system delivers more than one tenth the musical enjoyment, the differences in scale, bass extension, detail, and overall sound quality were as enormous as you would hope they’d be if you just dropped $4K on audio gear. If you pay 10 times more than I did for Hannah’s system, you have a right to expect a massively different experience, and you get it with the Duettos. Of course, I wish I could have compared them head-to-head with a similarly-priced competitor, but I don’t think I would have come away less impressed by what the Duettos can do from a pure sound-quality perspective.

Sonus faber Duetto: Conclusion

In addition to my music listening, I used the Duettos as TV speakers with mostly good results. The speakers reproduced film scores on a grander scale and with better tone than any soundbar I’ve heard, and dialogue clarity was good for Hannah, who sat right between the speakers. While I did all of my music listening from the sweet-spot, I am usually off to the side when we watch TV. As you might expect, the soundstage collapsed when I moved off to the side, and dialogue sounded a bit muffled. I think the Duettos would work as a TV audio solution in certain circumstances, for people who tend to watch TV alone, or who need to place the speakers closer together than would be ideal for music. I expect the typical Duetto buyer will be using them more for music than for home theater.

For music, the Duettos’ overall sound quality is simply superb. It had been some years since I spent a lot of time with a Sonus faber speaker, and I was expecting a more mellow presentation with softer high frequencies and a more laid-back attitude. That is not at all what the Duettos deliver. Instead, they offer a huge helping of clarity in the mids, impressively deep and punchy bass, and high frequencies that snap with enthusiasm. While I didn’t feel the need to add a subwoofer in Hannah’s relatively small living room (as I have with some other small speakers), the ability to to so will come in handy for folks with larger spaces and the need for bottom-octave performance. The treble presentation was occasionally a bit overeager for my tastes, but I know many audiophiles who would find it perfect — this is an issue of personal taste, not an issue of quality. While attaching an external streamer via Toslink kind of defeats the purpose of having an all-in-one active streaming speaker, doing so gave me an opportunity to test the Duettos’ optical input, which worked like a charm and sounded great when fed ones and zeroes from the Wiim streamer’s integrated Qobuz functionality. The Duettos’ industrial design is lovely, and the build quality and finish are very good, if not quite world class. As I mentioned earlier, this review was challenging because of the buggy software running behind the scenes, and the difficulties I had with the remote and touch controls. The mobile app was not available, and the web app was limited in what it could do. From a hardware perspective, the Duettos are a 5-star product. They make music sound fantastic, and they look good doing it. Just a few years ago, you couldn’t ask more of a speaker. But using an all-in-one HiFi system like the Duettos is as much about software as it is about hardware. Before I can give these speakers an unqualified recommendation, Sonus faber will need to fix the operational glitches, complete the app, and deliver a smooth, seamless, and frustration-free user experience. Knowing the company’s reputation, I have every expectation Sonus faber will do just that. These excellent speakers deserve no less.

The Score Card

The scoring below is based on each piece of equipment doing the duty it is designed for. The numbers are weighed heavily with respect to the individual cost of each unit, thus giving a rating roughly equal to:

Performance × Price Factor/Value = Rating

Audioholics.com note: The ratings indicated below are based on subjective listening and objective testing of the product in question. The rating scale is based on performance/value ratio. If you notice better performing products in future reviews that have lower numbers in certain areas, be aware that the value factor is most likely the culprit. Other Audioholics reviewers may rate products solely based on performance, and each reviewer has his/her own system for ratings.

Audioholics Rating Scale

• — Excellent
• — Very Good
• — Good
• — Fair
• — Poor

Metric	Rating
Ergonomics & Usability
Features
Build Quality
Appearance
Treble Extension
Treble Smoothness
Midrange Accuracy
Bass Extension
Bass Accuracy
Performance
Value