Five years in company's life is not much. These offering high-end devices introduce new products in more or less such intervals, so if company exists only five years that's truly short life and we should not expect too much from it. But obviously this is not a rule set in a stone and, with proper effort, it can be broken, or bypassed.
In the year of 2007, which means bit more than five years ago, the company Devialet SAS was founded in France. It appeared to be just another slightly eccentric French manufacturer (they all are, bit eccentric I mean), hoping to find its own niche on the market and in customers habits and preferences, somewhere between all other competitors that had been on market for long offering amplifiers, players and speakers. But it would be a mistake to think that – they way the company was founded, how it operates, what are its targets and purposes, and most of all their product – all that differentiates them from everything we, customers are used to. Surely there was one thing Devialet had in common with other companies – they, as many others, started with an idea.
In 2004, Pierre-Emmanuel Calmel quit Nortel R&D Lab to work on the first prototype of a new kind of hybrid amplification technology. The effects of his work must have been interesting enough for Mathias Moronvalle, a former Nortel colleague, to join this enterprise. In 2006, these two passionate engineers met other entrepreneurs – also musicians and audiophiles – from industrial design, marketing and management consulting: Emmanuel Nardin, Quentin Sannié and Manuel de la Fuente.
Usually the word 'hybrid' in association with amplifier is used when the preamplifier uses different technology than output stage. The most common solution involves tube preamplifier and solid-state output stage, although a Czech company KR Audio does it other way around.
In this particular case of Devialet 'hybrid' means something totally different, although popular association of this word is not that wrong. Company created and applied a technology called ADH, which reads as : Analog Digital Hybrid. This innovative technology allowed to combine an analogue, low-power, class A amplifier with mighty, digital, class D amp working in PARALELL.

I remember very well a maintenance engineer in Juliusz Slowacki Theater, where I worked at the time, telling me that he had a cool idea for an audio amplifier. In fact I was building my own small tube amp and he seeing it came up with an idea of a 'hybrid' amplifier, combining tubes a transistors, but his idea was to make them work in parallel. The key part of that project was supposed to be a small, class A SET amplifier that would work alone until no more than few watts would be required, but when there would be a greater need for power the second, solid-state amp would kick in. At the time I wasn't even aware that it wasn't the first time somebody came up with such idea – in fact it was presented for the first time in 1970ties by famous company QUAD, although they used two solid-state amps – a small class A one, and the second, much more powerful, working in a class AB. This idea was called "freeforward" and was implemented in power amplifier named 405. I have no idea what happen to this idea as I lost contact with this engineer many years ago, but in general, the idea of two amplifiers working in parallel seems to be still quite attractive for some designers as a solution/answer for weaknesses of classic designs.
Obviously it's rather difficult to realize that idea, to put it in practice as you can hardly find any such amplifier on the market. Except for Devialet D-Premier AIR – they used the idea and put in into practice designing a product that might, I'm not afraid to used that expression, revolutionize audio market: that's a hybrid, analogue-digital integrated amplifier, that includes also a D/A converter. You can feed it with analogue or digital signal. The latter can be delivered not only with S/PDIF (RCA and TOSLINK) cables, but also with HDMI, directly from a Blu-ray player. Designers used also their knowledge and experience from the field of wireless communication, as their product embeds Devialet AIR (Asynchronous Intelligent Route ), the exclusive Asynchronous Wi-Fi HD Streamer designed by Devialet.
To configure this device one needs to use a special application. Using it one can name inputs, assign functions to inputs, and even set a maximum power between 160 and 240 W. Considering that there are two amplifiers in kind of dual-mono setup, one working as "Master", and other as "Slave" the maximum power delivered at output might reach 500W per channel. The other key feature that makes this device different is its external design. When you see it for the first time you'll sure be surprised by its innovative look. Also using it is quite intuitive. My 18-years old son, a true fan w McIntosh and tube devices was simply stunned when he saw this flat, shining device on my rack (Devialet can be placed horizontally or vertically hung on the wall). He said it was the coolest thing I ever had in my system. He's 18, so he knows...
But I can totally understand his reaction. The enclosure is a solid aluminum casting and you can chose one of three available finishes: chrome silver, black mat, or white "High Gloss". It is possible to use two Devialets working as monoblocks. And while D-Premier looks awesome, its remote control, using radio waves to communicate with amplifier, is even cooler. Using it is amazingly comfortable, user-friendly – I miss it already. There is one more thing I would love to see – the reading from devices display – if I could have that on the remote too, it would be simply perfect.

As you already learned this is a unique, innovative, ground breaking device. It's supremacy on the high-end market is undoubtful, unless for open-minded people. Its unique character has been momentarily recognized by audio magazines around the world – its picture was featured on the covers of "Hi-Fi News & Record Review", "TONEAudio" and "Stereophile". Alan Sircom from "Hi-Fi+" magazine put it on the list of The 10 most significant amps in European history. Do I need to say more? Probably not, but I might still add that for the past two years Devialet D-Premier, presently in AIR version with all the upgrades introduced with the newest soft 5.7 (I forgot to mention that since Devialet emerged on market company still works on numerous improvements introduced via new software) is a part of Paul Miller's, "Hi-Fi News & Record Review" chief editor's, reference system...
It took Devialet engineers 3 years (2007-2010) to create the final product and introduce it to the market in 2010. Ever since many improvements have been implemented, mostly with newer versions of software (which is possible because a DSP processor is a heart of that device). So one might say that this product doesn't get obsolete.
The particular piece we've received for a test is a best prove of that. The original name of that device was D-Premier. Two years after it was introduced to the market a new version was offered, which in fact is an upgraded „old” version, and it changed its name to D-Premier AIR. You might have already guessed that this upgrade meant adding a possibility of wireless communication between Devialet and computer working as a source of a digital signal.
Most devices on the market use Apple AirPlay, which is configured in a way that forces user to use iTunes. It delivers decent performance but this way of delivering signal is surely far from being perfect. The owners of Devialet are people with their „roots” in telecommunication business. So it was to be expected that they would come up with something special. And they did – it's the 'AIR'. It is in fact a standard 802,11 b/g/n Wi-Fi. But in Air there is a Red Pine module working with the newest DSP Analog Devices Sharc circuit, that allows for asynchronous transfer of a signal using a single clock – the amplifier's master clock! After receiving signal goes to a buffer and is re-clocked to further reduce jitter. The only downside – for know the only software player that works with it is iTunes. The advantages of AIR are quite unique though: for one, even though we need to use iTunes it doesn't not process the sound (e.g. Kernel Mixer is bypassed), secondly, according to the manufacturer, in the near future we should be able to use also other software players. For know we can send only 16/44 signal but that is also supposed to change to allow sending even 24/192 signal via AIR. AIR starting from 5,6 versions allows sending 24/96 signal via Wi-Fi, and 24/192 that is automatically down-sampled to 24/96.

SOUND

Recordings used during test (a selection)

• Audio Accesory - T-TOC Records High Quality Data Master Comparison, TDVD-0002, DVD-R (2011), ripy FLAC 16/44,1, 24/96, 24/192.
• Random Trip, Nowe Nagrania, 005, CD + 24-bit WAV (2012).
• SATRI Reference Recordings Vol. 1, Bakoon Products, FLAC 24/96.
• SATRI Reference Recordings Vol. 2, Bakoon Products, FLAC 24/192.
• T-TOC Data Collection Vol. 1, T-TOC Records, DATA-0001, 24/96+24/192, WAV, ripy z DVD-R.
• Al Di Meola, Flesh on Flesh, Telarc, FLAC 24/96, źródło: HDTracks.
• Annie Lennox, Bare, "Limited Edition", RCA/BG, 22472, Copy Control Disc + DVD (2003).
• Ash Ra Tempel, Ash Ra Tempel, MG
• ART/Belle, 101780, SHM-CD (1971/2010).
• Breakout, Blues, Polskie Nagrania Muza/Polskie Nagrania, SXL 0721/2007, LP (1971/2007).
• Carlo Gesualdo, Madrigali, dyr. Rinaldo Alessandrini, wyk. Concerto Italiano, Opus111/Naïve, OP30486 (2000).
• Charlie Haden & Antonio Forcione, Heartplay, Naim Label, FLAC 24/96, źródło: HDTracks..
• Charlie Haden, The Private Collection, The Naim Label, naimcd108, 2 x CD (2007).
• Depeche Mode, Home, 74321501702, maxi-SP (2007).
• Jun Fukumachi, Jun Fukumachi at Steinway (Take 2), EMI/Lasting Impression Music, LIM DXD 038, silver-CD.
• King Crimson, Lark's Tongues in Aspic, Atlantic/WHD Entertainment, IECP-20220/221, "40th Anniversary Series", 2 x HQCD (1973/2012).
• Mark Knopfler, The Travelerman's Song EP, Mercury, 9870986, CD (2005).
• Metallica, Metallica , Warner Brothers Records, FLAC 24/96, źródło: HDTracks..
• Miles Davis, Tutu, Warner Brothers Records, FLAC 24/96.
• Pieter Nooten, Surround Us, Rocket Girl, rgirl85, CD (2012).
• Porcupine Tree, Deadwing, Lava, 93437, CD (2005).
• Schubert, Lieder, wyk. Dietrich Fischer-Dieskau, dyr. Gerald Moore, "Signature Collection", EMI, 55962 2, 4 x SACD/CD.
• Sonny Rollins, Tenor Madness, Prestige, WAV 24/96, źródło: HDTracks.

Japanese editions of CD and SACD available from

The experts seem to be some kind of giants, rising above problems concerning the rest of the population. At least in their area of expertise – they are, after all experts, right? Somebody like that doesn't have any weaknesses, is resistant to any kind of external influence, doesn't know what prejudice is – simply a walking perfection. Well... I wish it was true, I really, really do! My life would be so much simpler, everything would be simpler, easier, more obvious. Looking at such a device like a Devialet there would be no questions in my head like: "so light?", "so shining?", "so... 'digital'?". Regardless the experience and reason these questions must pop up in a mind of every person who has some experience with audio amplifiers. Experts, in this particular case, editors of audio magazines, are no exception.
That is why the sound of Devialet took me by surprise, as I'm pretty sure did everyone who gave it a try, „professional” audio guy or not. Why? Because what came out of my speakers reminded me of... what I usually get from high quality tube amplifiers. Although previous experiences with D-class amps did give me an idea of how such a device might sound, but in this particular case it was not about rounded treble, there was no softened attack, but about the general richness of the sound, warm vocals and rich, saturated lower midrange. And all that complemented with strong, open treble. For some time I even though that the tonal balance was set bit higher than in my reference amplification. But after giving my ears a while to accommodate to that sound this impression disappeared only to come back when I switched to my amp again. Sp its possible that in your system, your room sound might appear bit too lean or too bright. But there is a possibility to equalize that using different settings for bass and treble. Since the sound is processed in digital domain it effects a sound quality much less, than in case of classic, analogue amplifiers. So do that, if you need to, as it will improve the „comfort” of the listening significantly. In my case I preferred the sound without any equalization.
I think it was so because of this incredible resolution of the higher frequencies and because of how much energy they carried. But it's not only about that energy, that can be delivered also but much less expensive devices, but the energy combined with the „weight” of each attack, richness of each of them. These are attributed of tube amplifiers, no doubt. Even the best solid-states like my Soulution 710, Accuphase A-200, SPEC RSA-V1 (which is a class-D amp) are only able to present some approximation of that – it is still great, and for me it's enough, but still it doesn't sound in such a natural way like when delivered by high-quality SET amp. The more surprised I was with French amps presentation – not only a solid-state but a digital one.

That is followed by other attributes usually associated with tube devices.

The most important of them is how instruments are presented. And you can watch them closely, in the most intimate way, they are simply palpable. You can hardly ever see words 'digital' and 'palpable' used together, but Devialet is a prove that digital device can offer palpable presentation of instruments so the problem is not in the digital technique but in its implementation.

Of course the best recordings take the biggest benefit from it. I was bit concerned when I decided to play an Annie Lennox Bare, a recording coming from „dark times” of BMG, Sony and EMI, when each of those labels implemented some kind of „copy protection”. Specialized hackers could care less about this protections but for a regular music fan they were a true pain in the ass. In theory Copy Control was supposed not to effect sound quality, because it was based on adding some inaudible distortions that would make it impossible for computer to read signal from CD. Audible or not these distortions were a reason of significantly lower quality of the sound from such a CD... Anyway, I don't listen to Bare to often, and even if I do these are usually two pieces from an addition DVD, that were recorded before concert. These pieces are brilliant! Unlike the sound delivered by a CD. The French device was able to do something special about it (also about problematic Porcupine Tree Deadwings). Selectivity improved significantly, and as much as it was possible, also a resolution. But the most important improvement was the lack of this brightness and numbness of the sound. Now I could finally listen to it with pleasure, so I did as it was hard to predict if and when this could happen again. It was like the digital input stage of D-Premier was able to fix the mistakes made during mastering pressing.

So what about high quality recordings? Amazing! - you can simply reach out and touch musicians as they are right there in front of you in 3D. Dynamics is beautiful, which allows music to „breathe” and the listen to feel like he took part in some „live” event. Because of that I had to listen to a Charlie Haden's concert organized for his 50th birthday. It was incredible how real that sound felt like. Fantastic selectivity and resolution which resulted in very close, warm forefront and it gave me a very good idea of what and where was located on the stage. Especially that there wasn't even a hint of power shortage – Devialet delivered a truly great rendering of a live performance, with a small add-ons – wonderful timbre and slam.
What's more – this amp offers incredible dynamics. Only two amplifiers I know could compete with it - Soulution 710 and Accuphase A-200. Both have more sophistication, but none of them has this immediacy of dynamics changes, that French contender has. Devialet offers a hint of what it would be like if you listened to live recording at home with its full dynamic range, which of course would be quite difficult, especially over a longer period of time, as some fragments would be too loud, and some too quiet. If you listen to rock, or even jazz – there is no problem. The former is compressed already during production, the latter usually involves small bands playing is not so big rooms, so their real dynamic range is limited. That doesn't apply to classic music or soundtracks. If you like big orchestral performances you'd better have a large room for D-Premier. It will allow it to create something quite close to life performance, something very, very few other amplifiers can deliver. Have w tube amplifier play the same music and you'll know what I'm talking about. Although I am a great fan of tube amplifier, but I listen to music not only with my heart but also my brain and ears, and those tell me that some part of their dynamics is artificial, not the macro-dynamics, but micro-dynamics. Even if you get the impression of a „larger” dynamics it's rather because it plays louder.

To describe the sonic character of that device's sound I'll have to use words like „smooth”, „spacial”, „natural”. I think that I finally understand why D-Premier fitted so well into Paul Miller's system. On one hand its sound is powerful and open, and the other the roughness in the treble is somehow smoothed out. That should allow it to work perfectly with Bowers&Wilkins 802 loudspeakers in HFN&RR (the description of the system HERE) chief editor's system. Same goes for bass – rather slightly on a soft side, but delivered with amazing grip, at least down to 50 Hz. Bass isn't hardened as it never gets distorted in any way, at least not with my speakers in my room. The Jadis I-35, a great tube amplifier, that I auditioned shortly before Devialet, offered bass similar in character. The difference was that when it came to some high level moments bass got hardened, lost it's natural softness. Why? Because it required the amplifier to deliver too much current, which seemed to be a strong side of that amp. Devialet proved that French tuba amp had its limitations. Not because I-35 played it not so loud as Devialet, that I could feel that it offered less output power, but because the attack was hardened and the presentation got slightly messy at higher levels, which did not happen with innovative Devialet amplifier.
The D-Premier's ability to differentiate sound was amazing. The better recording the bigger, better, more natural sound it delivers. And when fed with hi-res files it improves even further. Most of files players, D/A converters have difficulty to present the difference between 16 and 24 bits, between 44,1 kHz and 192 kHz. Quit possibly the hi-res recordings are at least partially to blame here as it seems that many sound engineers still don't know how to make them right. I am 100% sure that all, or almost all hi-res recording that I acquired could still use remastering, improving. But there are few devices like Devialet, or recently reviewed Ayon system (see HERE), that are capable to prove why there is so much fuss about 24 bit word length and high sampling frequencies. The answer is simply – such recordings sound more natural. I would like to use a word „analogue sound”, but that would not be a proper description (see: Michael Lavorgna, The Road to Analog-Sounding Digital: Are We There Yet?, "Stereophile", January 2013, p. 3; see HERE). It's about more beautiful timbre, bigger space and loosing up a tie that CD standard tied up on our necks even if we did not realize that. There is still a long way ahead of us. Compact Disc can still deliver thing we did not dream about, but the innovative devices like Devialet point us in the right direction for the future.

Summary

Looking at the covers of audio magazines one might get an impression that almost every month there is some breakthrough in this industry, that the ultimate, perfect sound is at the grip of our hand. That's rubbish, don't believe in it! The reproduced sound is, and always will be a different universe that the one played live. Secondly that real breakthrough product appears only once in a while, long while. But when it emerges we need to cherish it, hold it dear, because only then something bigger, better, some block buster changing everything in this industry might really come. I don't think that Devialet requires caresses but I'd like to get in line to express my congratulations for its creators.
Make no mistake – that's not a perfect device. The soundstage would use some more depth, the differentiation of a timbre is not so sophisticated as when delivered by good SET amps. The lowest bass is also not so well differentiated and not so well defined as by high-quality solid-states. The selectivity is fantastic in Devialet's presentation but it's always the same, no matter what recording we play. It sounds beautiful, the problem is that it always does.
These downsides should not diminish the fact how innovative amplifier that is. OK, I wrote amplifier, but the D/A converter is also very good. When you hear the sound of this device you might think it comes from a small SET amp, with its incredibly palpable forefront, that seems to be slightly warm. Instruments seem to be within the reach of you arm. The resolution and selectivity are impressive not only considering the price tag, but also comparing it to other high-end devices. The ability of differentiation is amazing – it's like a tube amp inside a silicon chip!
The extensive functionality, releases of a new version of software and fantastic remote – that's all sings of 21st century. In connection with 19th century tube technique that it uses (virtually of course) to define the sound it offers a final effect different from everything else. A full scale revolution plus great aesthetic impressions – that's what D-premier AIR is, period.

TEST METHODOLOGY

D-Premier AIR is a device significantly different from anything else on the market, including other digital amplifiers. Its weight is not impressive, but it requires a high quality amp stand – that's what the distributor, Mr Jarek Orszański, told me before test and what I can hereby confirm. I used the Acoustic Revive RAF-48H stand. The power we deliver to French device also matters.
Usually I use the Acrolink Mexcel 7N-PC9430, as that's the best power cable I know, and it works great in my system. But the Distributor recommended the Synergistic Research Tesla SE Hologram A with active shielding, powered from external power supply. So I decided the run the test in the recommended setup. A large IEC plug forced me to disassemble a plate covering sockets. Since speaker posts are placed quite close to each other I was bit afraid to use my reference Tara Labs Omega Onyx cable. Instead I used Acoustic Revive SPC-PA. Often with digital amplifiers there it's a challenge to chose proper cables – low pass filters (LC) in the output combined with cable's capacitance and inductance often influence linearity of the signal. But there is no filter in D-Premier's output (another of Devialet's own solutions) so I wasn't afraid of any mismatch.
Although the device sports analogue inputs, including phono, in fact it's rather an amplifier with build-in D/A converter. Of course you can use a turntable or other analogue source and as long as the primary one is digital its fine. But the primary source should be digital and that's why I used a Philips CD-Pro2 transport in my Ancient Audio AIR V-edition CD Player as one source and a file player – the Ayon NW-T via buffered S/PDIF tube output as a second.
I did an AB tests, with A and B known. I used 2 minutes long music samples. My reference devices were my own two box amplification - Ayon Polaris III [Custom Version] + Soulution 710, and a tube amplifier Jadis I-35.

DESCRIPTION

Pierre-Emmanuel Calmel during interview given for John Atkinson, "Stereophile's" chief editor, presented many details regarding the design of the Devialet, so I'd like to use that. You can feed D-Premier either with a digital or analogue signal. The analog input signals are converted to digital with an A/D converter, a Texas Instruments PCM4220, running at 96 or 192kHz—the former is the default—before being applied to the volume control, which operates in the digital domain and is implemented in a 32-bit floating-point DSP chip by Analogix, along with a soft-clipping function and crossover filters when required. All signals are then converted back to analog by two Burr-Brown PCM1792 chips—a high-quality, 24-bit, two-channel, current-output device operating at up to 192kHz. Just half of the DAC is used for each channel, and the current output of the DAC is converted to voltage with a resistor and fed directly to the class-A amplifier—the analog signal path from the DAC output to the loudspeaker terminals is only 2" long. In effect, the DAC swings the high voltage required to drive the speaker output, and the class-A amplifier therefore works at unity gain, as a voltage follower, so that its performance can be maximally linear at high frequencies. As Mr Calmel said there are only 2 resistors and 2 capacitors in the signal path! Classic amplifiers of that kind have their problems as they generate high-frequency noise at the output, which forces designers to use low-pass filters. But there are none in D-Premier. Instead Class D stage is fed by digital processors, so that it receives a digital 300kHz PWM (pulse width modulation) signal.
This device is equipped with linear power supply. This type of PS i well known and widely used in military and health care devices, and in audio it's been used most of all by two companies - Linn and Chord Electronics, so happens, that both companies are from Great Britain (Scotland and England). The PS used for D-Premier delivers 600 W constant power and 2100 W peak power.

The shape of D-Premier AIR is also quite special – it is flat and square. On top there is a translucent window with a display placed under it. It allows the user to read (among other things) the volume, and the chosen input. The volume can be set in the range between -97 dB and +30 dB, with 0,5 dB steps. Signals from analogue inputs beyond 0 dB, are compressed, and at +30 dB gently cut-off. The elegant circular display orients itself if you hang the D-Premier from the wall. When a signal is received from a digital source the name of particular input is colored in red and the link between source and amp is established and than it turns black. There is a piece of information that is not, unfortunately, displayed – the word length. But since newer software versions allowed to read a sampling frequency it is possible that this „lack” will be fixed in the near future.
All sockets are placed on the back panel – impedance matching transformers are used for all digital inputs. The access to the sockets is really simple as the part of the cover is fixed only with magnets so it can be easily taken off. The back panel is quit small which leaves not to much room for sockets and thus these have to be placed close to each other – the power cable delivered by Distributor had a large IEC plug so I had to take this part of a cover off to plug this cable in. There are as many as 8 digital inputs: AES/EBU, 4 x S/PDIF (RCA), 2 x S/PDIF (TOSLINK) and HDMI. All of them accept a PCM signal up to 24/192. So before one can send a signal from DVD or BD player it has to be converted to PCM (check the menu of the player). There is also a HDMI output that allows to send an audio and video signal to a projector for example. There is also an analogue input that can be configured (via menu) and a regular linear input, or a MM/MC phonostage input. The digital input can be configured as analogue input, also for e second turntable, or, if you have a 2.1 system, you can use it to SEND an analogue signal to a subwoofer. D-Premier sports single speaker posts.

I've never seen anything like that before. A pure perfection.