The Audio Beat reviews the dCS Bartók APEX

“It’s been just over forty years since advertisements for the first CD player appeared, promising “perfect sound forever.” An ironic retort to that marketing claim finally arrived this year in the form of a graph showing that sales of vinyl records have now exceeded those of the compact disc for the first time since 1988.

It’s easy, in hindsight, to mock those of us who initially fell for that promise of perfection, but, in our defense, vinyl playback can be a monumental pain in the ass. The romance of records pales a bit once you’ve accidentally broken the stylus of an expensive phono cartridge or shelled out considerable cash for reissues that sound flat and lifeless.

It’s true that the best LPs can be awe-inspiring, but the very scarcity of high-quality pressings makes it impossible for music nerds like me to be fully satisfied. We’re stuck with digital, with all of its numerous flaws, because this medium provides its own magic, including access to virtually every recording ever made at the touch of a screen. An insatiable hunger for music of almost every kind is why people like me are still willing to spend considerable resources on digital audio gear.

Ironically, the more great vinyl I buy, the more I strive for better digital playback. If you’ve ever experienced the emotional impact a good analog recording can have, there’s no letting go of the promise that millions of archived digital albums could finally be converted into the kind of moving music that touches hearts and souls.

That need to connect with music is one of the reasons the dCS Bartók 2.0 headphone amplifier and streaming DAC is my current reference. Of the dozens of digital audio converters I’ve either owned or auditioned, the Bartók packs the most features and comes closest to hitting the musical bull's-eye. When I wrote last year about Bartók’s latest 2.0 firmware upgrade, I was particularly impressed by the luxury of dialing in its various sonic filters and algorithms to match my family’s aural preferences. With Bartók, the developers at dCS have managed to put cutting-edge psychoacoustic technology, a highly transparent headphone amplifier and a glitch-free streaming system into a convenient package that marks all the boxes on my form-and-function checklist.

Bartók 2.0's less-fatiguing glimpse at important musical details had me ready to step off the digital upgrade merry-go-round -- until last year, when dCS announced its Apex hardware upgrade project for the Rossini and Vivaldi platforms. At the time, company officials also said that Apex simply wasn't compatible with the Bartók architecture. While users like me nursed our disappointment cocktails, dCS engineers and developers persisted in solving the problem and, in February of this year, unveiled Bartók Apex ($20,950 without headphone amp, $22,950 with, and $9000 to upgrade Bartók 2.0 units to Apex). Owners who purchased a Bartók after August 15, 2021 should contact their dealers for special upgrade pricing.

According to dCS, the first area that engineers tackled during Apex’s research-and-development phase was the reference power supply. After making some significant adjustments and enhancements there, they made extensive modifications to the summing and filter stages, as well as the output stage responsible for buffering analog signals generated by the Ring DAC. The output stage was also redesigned to better interface with external equipment, enabling it to drive significantly more current despite the varying input characteristics of external sources that can pose stability problems in lesser DACs. 

Additionally, the Ring DAC’s summing stage has improved isolation from the outside world to optimize its performance and accommodate uncertain loads that cable-and-amplifier combinations can present. Other changes include replacing individual transistors with a compound pair to improve symmetry and linearity, and adjusting the layout of components on the circuit board. As a result of these major changes, the new analog board of the Bartók Apex is quieter than that of previous versions, and its linearity has been improved in the second harmonic by over 12dB.

If you think all of that tech talk is a bit overwhelming, you’re not alone. I reached out to dCS’s John Giolas for a bit of perspective. Giolas explained, “Linearity is expressed as a number, which is abstract to most audiophiles. The previous Ring DAC was already state of the art in terms of linearity. The Apex version is greater than an order of magnitude more linear.” As a result of that improvement, Giolas says that listeners to the new Bartók Apex should perceive a lower noise floor and fewer digital artifacts masking low-level detail. “Many of these audible improvements are directly related to the increase in linearity.” Beyond the improved linearity, Giolas says that the Apex Ring DAC is more stable and impervious to outside interference generated by the cables and electronics to which the DAC is invariably connected.

When I last spoke with Giolas back in 2022, I asked him how Bartók 2.0’s performance stacked up against dCS’s more expensive Rossini 2.0 DAC. At that time, he estimated the Bartók’s firmware upgrade brought it to within “85-87 percent of the Rossini.” When I posed the same question about the Bartók Apex, Giolas replied, “It’s better than Rossini 2.0.” So, naturally, I was eager to hear for myself just how far the dCS team could push the performance of a DAC that was already operating at the cutting edge.

It should come as no surprise to seasoned listeners that the brand-new Bartók Apex unit I received sounded less than ideal right out of the box. Because Apex represents a serious hardware overhaul, the review unit initially exhibited a brittleness in the midrange, gave off a metallic sheen in the higher registers, and struggled to convey fully the wide dynamic range of my own well-broken-in Bartók 2.0. All of those distractions began to disappear gradually during the 100-hour break-in period, and performance steadily improved for an additional 200 hours.

In the context of my audio system, the sonic payoff of the Bartók Apex upgrade was immediately apparent. Backgrounds were noticeably blacker, and instrumental tone and timbre were more realistic. Whether heard through speakers or headphones, the Apex version exhibited a smoothness and liquidity when producing higher frequencies that made Bartók 2.0 sound a bit rough around the edges by comparison. Bartók 2.0’s already hefty bass performance was given more texture and punch by the new hardware modifications. Also readily apparent was the expansion of the soundstage in all directions. The presence of the back wall immediately behind my equipment rack is unavoidable, but Apex seemed to push it back a foot or two.

One of Bartók 2.0’s strong suits is its layered presentation of detail. Apex ups the ante. For example, on Heather Ridgon’s Young and Naive [Tidal 16-bit/44.1kHz stream], her singing partner’s voice on “Couleur Cafe” is more easily differentiated when heard through the Bartók Apex. With Bartók 2.0 handling the data conversion, Rigdon’s contralto voice sounds as though it’s coming primarily from her chest throughout most of the album. By contrast, Apex still delivers the depth of her range while also revealing the throaty nuance of her delivery, as she chooses to open up some phrases for seduction while clipping others for a dramatic effect. All of these revelations amount to a more sensually engaging listening experience.

The Bartók Apex’s sonic character reminds me of the magic I’ve heard from single-ended-triode power amplifiers. My immediate response to recordings sent through a 300B or 2A3 tube amp is more visceral and less intellectual; the Bartók Apex leans more in that Technicolor direction than any previous solid-state DAC I’ve heard. For example, listening to Julian Lage’s Fender Twin Reverb amplifier on View with a Room [Tidal MQA 24-bit/96kHz stream] triggers vivid memories of the first time I played a Stratocaster through a decent tube amp.

Bartók Apex produces a more believable facsimile of the luscious textures, pleasing harmonics and cavernous resonances vintage tube-based guitar amplifiers can deliver. This luxurious glow can also be heard on Morphine’s “You Look Like Rain” from their Good CD [Rykodisc RCD 10263]. Through Bartók Apex, Dana Colley’s baritone sax lines are burnished with caramel tones and a you-are-there presence I’d never noticed through my system before.

Sufjan Stevens’s “Come on! Feel the Illinoise!” from his Illinois album [Qobuz 16-bit/44.1kHz stream] poses a serious challenge for any audio system and especially for a digital streamer. This baroque pop masterpiece is dense and intricate. When using it for reviews, I question whether the equipment can flesh out the recording’s detail without overemphasizing one particular element at the expense of the important cohesion of the track’s intricately syncopated, rhythmic thrust. If a DAC’s timing is not up to the task, the music will sound muddled and confused. Through the Bartók Apex, Stevens’s production and engineering deliver a dizzying calliope of tonal colors, layered sound effects, and luscious orchestral variations and textures. Based upon performances by Stevens I have attended, the presentation of the Bartók Apex more closely re-creates the forceful slam and three-dimensional presence of instruments that are the hallmarks of Stevens’s live shows.

Whenever I have a uniformly positive reaction to a piece of audio equipment, I always feel the need to get second and third opinions. Several of my friends whose audio systems bear no resemblance to my own were happy to weigh in. While this process is by no means scientific, I always learn something about my own biases and discover elements I overlooked. Everyone who visited immediately commented that the Bartók Apex was more musically involving than Bartók 2.0. Beyond that, each listener focused on a particular aspect of the Apex presentation that I suspect spoke more clearly to their own respective musical priorities. The tube fanatic who loves all things analog remarked on the warmth and three-dimensionality of the Apex; the Magnepan owner noticed Apex’s greater transparency to source and more accurate reproduction of acoustic instruments; the speaker builder pointed to how much tighter and textured the bass frequencies had become, and how the room could be more easily pressurized at lower volumes.

About those bass frequencies. One of the reasons I purchased my Bartók 2.0 was that it delivered the most realistic, substantial bass of any digital playback platform I’d ever heard. Much to my surprise, Bartók Apex adds to bass frequencies the kind of goose-bump-inducing realism that I’ve only heard when high-quality subwoofers are employed. Through the Bartók Apex’s new analog stage, bass notes are not louder or more prominent; they are more extended and believable. Low-bass notes that were mere pulses through Bartók 2.0 are distinctly melodic through Bartók Apex. Prior to hearing Bartók Apex, I would have credited or blamed my Wilson Audio Sasha 2 speakers or my HiFiMAN SE-560 headphones for this level or bass reproduction. It turns out that these transducers are capable of much more than I ever suspected.

What surprised me most about some of my friends’ comments was that I rarely think of the qualities they mentioned when evaluating digital sources. Those reactions are more often the result of auditioning new amplifiers or speakers. Hearing visitor feedback reminded me that an audio system’s source component is at least as important as whatever speakers happen to be in the chain.

As part of my quest for better digital sound over the years, I’ve sent several DACs away for modifications and upgrades. Whether it was switching to exotic capacitors, adding a better power supply, enhancing a tube stage, or using audiophile fuses, the audible improvements the changes produced varied widely. Sometimes the results were dramatic, while other times the needle only moved a little. Because Bartók Apex unearths so much more information buried in digital files and presents that information with such palpability, it startled me and my guests by triggering new responses to music we’d all heard many times before. Listening sessions with Bartók Apex quickly moved us from cognitive analysis to a more emotional appreciation of an artist’s performance. If you’re looking for the kind of audio gear that makes it easier to fall under the spell of music’s magic, the Bartók Apex DAC should be at the top of your audition list. I’ve already sent in my Bartók 2.0 for the upgrade."

You can read the full review online here: https://www.theaudiobeat.com/blog/dcs_bartok_apex.htm