dCS Bartok

Know your reviewer​

Hi there, as I am not a professional reviewer, I wanted to prefix this review by introducing myself a bit, so that you know what biases I have, what physical limitations I have to work with, and most importantly, what is my end goal. I put the following section into "spoiler" tags, so that those who do not wish to read about me, do not get distracted from the dCS Bartók's review.

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dCS Bartók's features and specs​

Build quality and port selection​

Bartók weights 16.7kg (36.8lbs), and measures 44/43/15cm (17.5/17/4.6"), which is a lot. It is much heavier and bigger than any other headphone DAC or AMP I have owned before. In the picture, you see a comparison with Chord Hugo TT 2. Bartók comes in two colours - silver and black.

As for ports, on the front you get a single ended 6.3mm and balanced/differential 4-Pin XLR. On the back, there is an RJ45 ethernet port for streaming capabilities, an USB type B port, SPDIF on RCA; BNC; and Optical Toslink, as well as 2x AES. For outs, you get single ended RCAs as well as balanced/differential 3-Pin XLRs.

Bartók also has an option for external master clock input, which costs additional 8k (Rossini) or 14k (Vivaldi), neither of which I had tried.

Streaming, upsampling, filters and advanced features​

One of the biggest reasons for all-in-one device like this is so that you don't have to worry about buying other devices that perform those functions. DAC/AMP combos are known and common (like Chord Hugo TT 2), and upsamplers exists (like Chord M Scaler), as well as streamers do (Chord 2go/2yu, or Pi2AES, or many others).

However, Bartók comes with all of the above - it is a Roon endpoint, supports Airplay and Spotify Connect (I suspect for the upcoming Spotify lossless), as well as comes with its own iOS and Android app called Mosaic. With it, you can connect UPnP, or stream Qobuz/Tidal/Deezer). I have been using it mainly with Roon and it worked flawlessly. It even lets you configure automatic standby after N minutes of not playing songs. I have also used it with Airplay and it worked nicely, albeit I had to disable "buffer" mode to have no video delay that would make people talking be delayed (lip sync).



Bartók automatically upsamples all PCM audio to DXD (352.8kHz / 24bit), but leaves DSD and DSD64 unchanged. This is similar to Chord Hugo M Scaler, which does a similar thing with its upsampling to 768kHz, trying to approximate perfect sinc function with its WTA filter. I am not sure if dCS's intentions are the same, or if upsampling here is for some other reason. As a side note, I have auditioned M Scaler for a week with my TT2 and found the upsampling make the sound more rich/lush, which I did not always prefer (for EDM that is).

What is interesting is that Bartók offers an extra DSD section, that you can use even if you are not feeding it with DSD music. It will come after upsampled PCM and will offer its own filters (F1 to F4). While talking about filters, PCM itself offers F1 to F6, plus one for MQA. As for input formats and files, PCM up to 384k is supported, DSD up to DSD64 and also MQA as well. All of my music is PCM up to 192, so I have not tested anything else, nor MQA (I subscribe to Qobuz, not Tidal).

Bartók also supports channel and phase swap, has burn in sequence that you can use for your headphones, but most importantly it supports channel volume balance for those who have hearing loss on one of their ears, in order to make the sound appear dead centre.

Display, quirks and bugs​

The digital display is very nice, it shows you what song you are playing from Roon, what is the bitrate and bitdepth, but no album picture. It also shows you what clock you are on (if you have external clock for example), what PCM filter you have in use, if you have channel or phase swapped, as well as your cross-feed/Expanse setting. What it does not show you is current volume (that is only on USB input, not Network), nor what upsampling you have (DXD or DSD) - which I find weird, for that you need to open iOS/Android Mosaic app, or go to Bartók's menu.

One thing I do not like is how Bartók makes a relay click whenever it changes the bitrate (no click on bitdepth change), so if your music keeps going from 44.1k to high res, you will hear a click every time that happens (not for 16 bit to 24 bit though). The buffer mode adds a tiny bit of a delay (less than a second) and is there to help to reduce audible clicks in the music playback itself, when bitrate changes. I have however disabled the buffer, as it was annoying to be always enabling it for music, disabling for video, and I have never heard any playback clicks (else than physical relay click) when bitrate changed.

The only bug I found (and reported to dCS) is that when I finish playing music with Roon and swap to watching a Youtube video over AirPlay, it still shows what is being played (albeit paused) via Roon. However, if I restart the device and just play via Airplay, the metadata is available and correct.

What I like though is how you can change volume either on Roon or with Airplay device (like your iPhone or Mac) and it will change volume (and show you in dB) on Bartók's display directly.

Headphone amplifier section​

Bartók's amplifier is surprisingly powerful. Not as powerful as Violectric V281, nor Chord Hugo TT2's rear XLRs, but plenty for most headphones, and even Abyss AB-1266. If you use it with its balanced/differential 4-Pin XLR outs, you get 2.8W with a 66Ω load, and with high impedance headphones that need high voltage swings you get 13.6V rms and for low impedance headphones that require high current swings you get 200mA rms.

I was originally worried that Bartók wouldn't be able to drive my AB-1266, that are known to scale with more power, but I was wrong. Bartók drives them better than my Chord Hugo TT 2 rear XLR's (that output 6W into them). Abyss team went on record (in one of their Youtube videos) that XI Audio Formula S is rated at around 2W and is their recommended solid state amplifier for AB-1266, so clearly 2W is enough. I do not know, however, if Susvara owners would be satisfied here.

Probably worth mentioning is that this is Class A only until 150mW into 32Ω load, after that, it goes Class AB.

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dCS Bartók vs Chord Hugo TT 2​

So how does it sound? How does anything sound, unless you compare it to something others know? I do recognise that I am here comparing 5k Chord to 20k dCS, but as you read already above, for me, the goal is to build "all-in-one" system and from Chord's current offering, TT2 is kinda the only option for AB-1266. Yes, Dave with M Scaler would be more resolving combination, but would also require an external amplification of the same calibre, something like Riviera, Bakoon, Woo Audio or XI Audio.

Before I go into details, I would like to say that I try my best to audition new gear with my wallet. Not only building a better system, but a system that I consider a "no brainer". For example, TT2 is an incredible value for money, but adding M Scaler did not feel cost effective (also it would not be all in one system anymore). I did listen to Dave at CanJam 2016, but that was a long time ago, in a loud environment and with a different pair of headphones. For that reason, I am apologising for those who own Dave setups and consider them better than Bartók. But for me, cost of streamer+HMS+Dave+amplifier would end up costing more than Bartók and would be a set of boxes that I would need to cable appropriataely. I recognise that this way you can built a system you sonically prefer, but it won't be a simple solution anymore.

Now that we got this disclaimer out of the way, let's compare Bartók to TT2. Since I am not a professional reviewer, I will struggle in this section putting my thoughts into words that others will recognise. Describing audio is difficult for me, so I will focus on my experience and making analogies to other things, like sport cars.

Acceleration and handling​

If you look at a sport car, what do you expect from it? For me it would be how fast it reacts to my throttle control and how well it handles. It needs to react lighting fast, I need to be able to index the position of the car precisely, and want the car to hold me tight, so that I can push my limits as high as possible. Bartók is like Tesla PLAID or a proper hypercar, it accelerates from 0 to 100 in 2 seconds, has very sharp steering and does not roll in corners. What I am trying to say is that Bartók is capable of playing aggressively, produce sharp music, give you a punch when you ask for it (or music dictates). Songs have incredible sense of speed, aka PRaT, and the low end is very well controlled and punchy. Compare that to TT2 (or with HMS), it feels more sluggish, taking its time, being warmer and more lush. It feels as if it was not adapting to the requirements you want it to. It is still a sport car, but not a hypercar.

Comfort and seating position​

What surprised me the most was when I played vocal focused tracks (mids are known to be AB-1266's weakest point) and they sounded natural, like a human voice. Analogy I would like to illustrate here is that it feels like Bartók is able to transform into a luxurious SUV, where you do not feel the road surface at all, and sit as high as a king on his throne. And all of this is being done song by song, as if Bartók knew what I expect from that song. You know the feeling when your expectations are met, and when they are not. You get disappointed when they are not met, you are happy when they are met, but when they are exceeded, you get very excited. That's how I feel when playing ANY song on Bartók. When I was talking to friends before setting up the home listen, they warned me that Bartók will sound more analog/sweater/fuller, compared to if I went into Dave. They also told me that adding M Scaler to TT2 will make it sound less harsh, and more analog like - but song by song, poorly recorded ones still sounded bad, and well recorded was a hit or miss, sometimes I preferred HMS+TT2, other times I did not. With Bartók, all songs sound wonderful, rich, sharp, they sound exactly like I would expect them to sound. This is the quality I did not expect from Bartók to be honest, this predictive nature of knowing how I will like the song to sound, as it if read my mind. Someone told me that this is called transparency, when your headphone system disappears and you just listen to music, not the gear. I don't know if this is the definition, but to me, it blew my mind.

Crossfeed implementation​

I never liked Chord's crossfeed implementation, to my ears they just collapsed soundstage (most people hear opposite here), and Bartók did exactly the same on its crossfeed setting, but not in its Expanse settings. dCS went into science of how this works in their whitepaper, but I must say, it works much better. It makes music sound like it was coming out of a speaker in front of me, including reverb and the low end. I do not prefer it with all songs out there, but some rock just makes me feel I am in the concert haul.

DXD/DSD and filters​

I was told that I would hear a difference between filters and DXD/DSD setting after a while, but it hasn't happened yet. But I also do not hear a difference between Chord's filters either, so there is that.

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Bartók + AB-1266 TC vs Sennheiser HE-1​

This one is from memory. I listened to Sennheiser for half an hour at CanJam 2016, so take this with a grain of salt. The price difference between dCS Bartók plus Abyss AB-1266 Phi TC and Sennheiser HE-1 is kinda 40k (60 - 20), so one could hope HE-1 is much better, and I don't think it was. I am mentioning this particular system because that would be the ultimate "all-in-one" headphone system, that I do not have to worry about changing cables, fiddling with headphones and such, all designed by the same company. Mind you, I have never auditioned Hifiman's Shangri-la (costs 50k), so can't compare with that one. My issue with all electrostats I have tried (HE-1, 009 with BHSE) is that they lack bass. They are very fast, that is true, so the treble is accurate, but not the lower end. Sennheiser's HE-1 was not any different.

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Summary​

Most of you will think, why don't you add a well known amplifier, like Woo Audio WA33, or Riviera AIC-10 and the answer is that I do not want to. I am trying to build a system that is as much as possible all-in-one and includes Roon streaming, quality DAC and powerful enough amplifier for my Abyss AB-1266 Phi TC. So far I have only found two systems that can do that - Chord Hugo TT 2 (need to add streamer) and dCS Bartók. How good is Bartók compared to TT2? To my ears, it is a night and day difference. People talk about the law of diminishing returns and trust me, I never wanted to spend more on electronics than on transducers, but now I have.

The main quality of Bartók over TT2 is how it (somehow) knows the sonic representation of the song I will prefer. Songs that I like aggressive/sharp will sound exactly like that, and the ones I want full/rich/lush, will do that as well. TT2 wasn't as good at this, there I felt it is adding a flavor to my music, sometimes desired, but sometimes unwanted. I used to own Hugo 2 before TT2 and a jump in quality for sonic characteristic wasn't that high, but I needed it for its powerful amplifier (that is also why I did not end up going for Dave).

Not only Bartók comes feature packed, it also is powerful enough for AB-1266, which was a surprise to my ears. TT2+AB-1266 is a 10k setup, which is a good value in my opinion. But, Bartók+AB-1266 is a 20k setup, I think all lovers of all-in-one solutions should work towards to - it is that good.

You may ask, what does my wife say? She has been supportive of my hobby for years, but never got it - until now. When I asked her to listen to Bartók she was amazed how good it sounds (she normally listens to Airpods mind you), but when she switched back to TT2, she called it flat, like a fizzy drink vs flat one. The enjoyment was gone for her. I think she was a bit too harsh to the system, but at least honest and showed me that not only a person who is into audio, but also someone who isn't can tell the difference. What surprised me even more is that she asked me to buy tickets to the next CanJam so that she can listen to some other gear, now that she heard how good things can sound.

For those who are into multiple pieces, I hope this review was not a waste of your time. I believe you can get good results from other TOTL dacs (like Holo May, HMS+Dave) and TOTL amps (Riviera, WooAudio, Bakoon), but I think no one can deny that Bartók is a nice all-in-one package and those who want their life simplifier to owning just one box, should give it a listen.

Bartók has convinced me so much so that I have placed an order for a black unit.

Introduction
The past decade has been somewhat of a golden age for headphone audio enthusiasts. In addition to the plethora of new companies and products on the scene, the level of innovation and performance has also significantly gained pace. It’s not a stretch to say that the sound quality we can achieve with our headphone audio rigs today is something that we could only dream about just a few short years ago.

One of the areas that has seen such dramatic change has been digital audio. I remember the excitement surrounding the first asynchronous USB DACs and the feeling that digital audio was finally coming of age and would someday be able to approach the performance level of vinyl playback. I also remember hearing about Cambridge, UK based dCS and was familiar that they were the first company to introduce asynchronous USB to a standalone DAC, called the Debussy, back in 2008.



Traditionally known in the hi-fi world for their proprietary, and fully upgradable, dCS Ring DAC, dCS is also known for its position at the upper echelon of the high end audio market. For reference, the full stack Vivaldi digital audio playback system (DAC, Transport, Clock, Streamer) costs over $115,000 with the Vivaldi DAC alone costing $35,000. In developing the Bartok, dCS set out to design a standalone, one box solution that would be able to provide a large dose of trickled down performance of the full stack Vivaldi system in a package that would appeal to a variety of use cases, including streaming and headphone audio listening.



Over the years, we’ve seen several two channel audio companies dip their feet in the water with dedicated private listening rooms at various CanJam shows around the world. And until recently, it seemed that the primary goal was to introduce head-fiers to the world of two channel audio with the rationale being that headphone enthusiasts would eventually “graduate” to two channel systems when they were able to. And yet, there seems to be a recognition of the high end enthusiast headphone community as its own niche market. A market that is asking for products with more innovation and better performance along with truly high end and aspirational products that also imbue a luxury lifestyle and strong pride of ownership.

The dCS Bartok would fit into this category and would squarely aim to appeal to the headphone enthusiast looking for an end game DAC to build a rig around or someone looking for a one box solution as the Bartok includes an excellent built-in headphone amplifier and streamer.

The Bartok was released in 2019 and can be purchased either as a DAC only version (US MSRP $14,500) and as a DAC with Headphone Amplifier version (US MSRP $17,250). The subject of this review is the DAC with Headphone Amplifier version and encompasses:

• The dCS Ring DAC, which is the very same one found in all dCS DACs including the flagship Vivaldi.
• A Streamer that can be used with the main streaming services and as a Roon endpoint.
• An in-house designed Class A headphone output stage that uses an all discrete transistor design along with its own dedicated power supply.
• An app called Mosaic that enables full control over the digital audio system.

I first heard the dCS Bartok at several audio shows in 2019 including CanJam and Munich High End. And just prior to CanJam London 2019 (one of the last CanJam shows prior to the involuntary pause caused by COVID-19) I had the opportunity to visit the dCS headquarters in Cambridge and came away extremely impressed with the engineering focus of the company and the story behind it.



After spending several months with the Bartok in my home system in 2020, I’m better able to share my longer term impressions.

Unboxing and First Impressions
The Bartok is shipped double boxed with a white dCS box containing the Bartok protected by an exterior shipping box. The unit is well cushioned in the box with foam and comes wrapped in a black fabric drawstring bag. There is an excellent and detailed 54 page user manual along with Quick Menu guide and Mosaic control one sheets.

The first noticeable thing when lifting the Bartok up for the first time is its heft and physical size. It's a weighty beast coming in at 36.8 pounds (16.7 kilos) with dimensions of 17.5” x 17” x 4.6” (444mm x 430mm x 115mm). The large dimensions of the unit make it ideally suited for a dedicated audio rack.



The Bartok is beautifully finished in thick, machined aluminum and feels incredibly well made and rock solid. It eschews the more sculpted fascia of its higher end dCS siblings and instead opts for a flat front panel with a hi-res screen on the left, 6 small metal buttons, two headphone outputs (one balanced, one single ended), and a silky smooth rotary volume control on the right. Although dCS does sell a dedicated remote control as an add-on option, all of the controls can be easily accessed either through the front panel menu system or the Mosaic app. There is also the possibility to connect a universal remote control and I was able to connect a Harmony 700 that was lying around with relative ease, although in my application it wasn’t fully necessary as my audio rack is placed within arms reach of my desk.

Setup
The Bartok serves as the hub of a digital audio music playback system. Like many others, I listen to music and media from a variety of sources including playback of lossless audio files stored on my computer’s hard drives, streaming of audio files from Qobuz, as well as content consumption from YouTube and digital audio playback from my Smart TV apps such as Netflix, and Amazon Prime Video. With the Bartok I can seamlessly switch the input source for my given application and for music specifically, I can use the Bartok as a Roon endpoint to manage both my hard drive based music files as well as my Qobuz streaming.

The back panel of the Bartok contains the connections for balanced and unbalanced analogue audio outputs as well as S/PIDF (coaxial and TOSLINK), AES, and USB inputs for connection to the computer and/or formatted flash drive or NAS drive. There are also Ethernet and IEC connectors as well as connectors for adding an external Master Clock to get even closer to the performance level of the dCS Rossini and Vivaldi platforms.



To set up the Bartok in my system, I connected a USB cable to my PC and this connection called “USB 1” is the connection used when listening to music stored on my PC’s hard drives and consuming content from my PC system, which in my case is mainly YouTube.

Connecting an Ethernet cable to my router, I’m then able to use the Mosaic or Roon apps to control my stored music files as well as my Qobuz streaming. When using the Bartok in this manner, the input will switch automatically to “Network”.

For watching movies and shows on my TV, I have an optical cable connected to my TV and the “SPIDF3” connection on the Bartok.

I also have a set of RCA interconnects between the analogue audio outputs on the Bartok and the Auris Headonia 2A3 headphone amplifier. I can engage the Headonia by pressing the Output button on the front panel of the Bartok which toggles between the internal headphone out and the analogue outputs.

My listening impressions were mostly done using the Hifiman Susvara and Abyss Diana Phi, and to test out IEM’s, the Vision Ears Elysium and qdc Dmagic 3D. For the Susvara specifically, I also added the Auris Audio Headonia 2A3 headphone amplifier to compare with the Bartok’s internal headphone output stage. Finally, I compared the Bartok’s built in streamer to the Innuos Zenith MK3, a highly regarded, high end music server.

Sound Impressions
The dCS Ring DAC incorporated in the Bartok uses the same Ring DAC board found in the Rossini and Vivaldi DACs, albeit using a single power supply with a second power supply performing duties for the headphone amplifier. The Ring DAC uses a network of programmable FPGAs that are running proprietary dCS software that performs the digital to analog conversion as well as the digital filtering. One of the key advantages of the Ring DAC is its upgradeability via firmware updates.

Listening to the Bartok is absolutely breathtaking. dCS are somehow able to combine transparency and dynamic range along with beautifully rendered timbre, to deliver an incredibly realistic sound experience. And it does so in a relaxed and easy-to-listen-to-for-hours fashion. Music is conveyed with a broad palette of “color” and an impeccable sense of timing which results in the Bartok sounding organic and natural. And if the goal of a DAC is to bring us as close to the music as possible with the least amount of digital “noise”, the Bartok manages to accomplish this with aplomb and finesse

Using the dCS Bartok internal headphone amplifier
The headphone amplifier of the Bartok is an in-house designed Class A headphone output stage that uses an all discrete transistor design along with its own dedicated power supply. dCS manages to balance voltage and current requirements such that the Bartok can handle both high and low impedance headphones.

Depending on headphone used, the Bartok has 4 gain positions, from 0 (loudest), to -10, -20, and -30. In this case, I use the Susvara and the Diana Phi at 0 and -10, with the IEMs being at -20 and -30. The Bartok has (6) digital filters that provide slight, but perceptible differences in how the music is presented and these filters enable the end user to better match to their own personal preference. There is also a crossfeed filter and a recently updated Expanse filter options that provide 2 additional filters for headphone users. Although my personal preference is to listen without any of the crossfeed options, it's great to have the flexibility and with certain types of recordings, it's a welcome option to have.

The Bartok’s headphone amplifier is able to drive most headphones extremely well, and even with the hard-to-drive Susvara, the Bartok sounds incredibly smooth, fast, and tight, with very good dynamics. The Diana Phi is an especially great match with the Bartok’s internal headphone amplifier and I found myself switching between 0 and -10 depending on mood and music genre.

It was also a revelatory experience listening to the Vision Ears Elysium and qdc Dmagic 3D IEMs out of the Bartok. With both IEMs at a gain setting of -20 I still had plenty of volume range and both IEMs scaled significantly higher through the Bartok than out of the Astell&Kern SP1000, that I generally use for IEMs. Transparency, speed, dynamic range all increased along with a deeper and wider soundstage. Both IEMs sounded better than I had ever heard them and had zero background noise, with a completely black background.

Using Auris Headonia as external headphone amplifier
The Auris Audio Headonia 2A3 tube headphone amplifier (US MSRP $9,899) is a great pairing for the Hifiman Susvara. When using the dCS Bartok as a DAC only there are four gain settings for the analog outs and these settings are 6V (loudest), 2V, .6V, and .2V. When listening with the Susvara, I keep the setting at 6V which gives me a comfortable to very loud volume range of between 2 and 4 (out of 10) on the Headonia volume knob.

Adding the Headonia presents a slightly more three dimensional musical image that is simultaneously both larger and more diffuse, while at the same time adding a little more emphasis on the midrange and increased dynamics and slam. On the other hand the Bartok’s headphone amplifier shines with a slightly more intimate, faster, and tighter sound against a perfectly black background which is intoxicating.

Overall, the headphone output in the dCS Bartok is an excellent solid state amplifier in its own right. Many transparent solid state headphone amps sound excellent on a short listen but induce listener fatigue over time. The Benchmark HPA4 is one of my favorite solid state amps that is both transparent, dynamic, and non-fatiguing. And the Bartok’s headphone amplifier is very similar in this regard.



Comparing Streamers
I also compared the built in streamer of the Bartok with the excellent Innuos Zenith MK3 (US MSRP $4249) running both units with Roon as an endpoint. And while there are some minor differences in how music is presented, it’s somewhat of an exercise in splitting hairs between the two when comparing sound quality. The Bartok streamer works flawlessly with both music stored on my PC’s hard drives and in streaming my Qobuz files. One of the big differences between the two is that the Innuos unit has onboard hard drive storage and can also rip CDs directly to its internal storage. In the end, I believe that the added convenience of the Bartok’s built-in streamer would likely negate the need for a separate streamer for sound quality purposes alone, unless specific additional features are required.

Conclusion
The dCS Bartok is a truly spectacular product. Essentially, this distilled version of the flagship Vivaldi and Rossini digital audio platforms, provides a one-box solution for digital audio playback using the same upgradeable dCS Ring DAC as its flagship siblings. It’s not a surprise that the Bartok DAC is a stellar performer and worthy of consideration for any end game headphone (or two channel) audio rig. The real surprise is the quality and refinement of the headphone output stage and the streaming capabilities of the dCS Bartok which largely negate the need for additional components and cables.

Headphone enthusiasts are increasingly spoiled for choice with companies like dCS pushing the envelope of what’s possible in digital audio playback. It’s also great to see a high end audio company like dCS get more involved in the headphone audio space, with their development of the headphone output stage in the Bartok.

The Bartok should be on a (very) short list for anyone looking for an end game DAC and gets my highest possible recommendation.