Note: Measurements can be found through this link.

Reviewers' ChoiceAn unflinching commitment to iterative improvement is what sets “the best” apart from everything else, and in that respect, Devialet of France is competing only with itself. With a recent infusion of €100 million from a consortium of investors including Foxconn, Renault, and Sharp, Devialet’s aims clearly reach far beyond the listening rooms of audiophiles like you and me. Yet that show of confidence is predicated, in large part, on the success of Devialet’s Analog Digital Hybrid (ADH) amplifier, a patented circuit that earned its reputation for state-of-the-art performance in their line of Expert amplifiers, such as the 120, which I called “the single most impressive audio product I’ve ever spent time with” when I reviewed it in July 2014. Devialet claims that the newest iteration of the 120, the Expert 130 Pro ($7690 USD), is even better.

Devialet’s new entry-level amplifier is virtually identical in appearance to its predecessor; the sole difference is the color -- white, not black -- of its only exterior control, a teardrop-shaped Power/Input button. Unchanged from the 120 are the Expert 130 Pro’s polished aluminum case measuring 15.1”W x 1.6”H x 15.1”D and weighing 12.4 pounds, the circular OLED display on its top panel, and various connections. These connections include: Wi-Fi via Devialet’s proprietary AIR app for Mac and Windows operating systems; Ethernet (also managed via AIR); asynchronous USB; S/PDIF optical; 3.5mm optical/RS232 connector; RCA, which can be configured as line-level or phono inputs; and a pair of coaxial inputs, which can also be configured as preamplified analog outputs, while one of these inputs can also be configured as a digital output. The digital inputs support PCM signals up to 24-bit/192kHz; only the USB input can handle up to PCM 32/192 and DSD64. There’s also a slot for the SD card that Devialet includes with each 130 Pro, to configure the device to suit the listener’s needs (see “Setup”). Also on the rear panel are a grounding point, five-way binding posts, a trigger input, and an IEC power inlet for the provided AudioQuest NRG power cord.

Devialet Expert 130 Pro

Several years after the company’s debut, the look of Devialet products isn’t as provocative as it once was, but the slender case’s fingerprint-friendly mirror finish and chunky, wheeled remote control still look and feel terrific. Though the Expert 130 Pro can be mounted on a wall, most listeners will probably do as I did and lay it flat -- which makes reading its top-panel display impossible unless you hover above it. Given the 130 Pro’s flexibility, this mattered little to me, as explained below.

The Pro hardware platform and current software continue Devialet’s predilection for initialisms. Their Analog Digital Hybrid circuit is now called ADHV2, this second generation having a simplified class-A amplifier that passes signals through “two silicon junctions less” than the original ADH. The algorithm that sits between this hybrid amp’s class-A and class-D circuits is now 10-bit instead of 8-bit, thus, per Devialet, “multiplying the precision of the ADH core’s control by 4.” The updated class-D amplifier benefits from a power supply 50% larger than in the original ADH circuit, more gain in the ADH loop due to 14 inductors per channel instead of 12, and greater thermal efficiency. Devialet claims that their implementation of Texas Instruments’ PCM1792 DAC in a special gain circuit, which Devialet calls Magic Wire, results in a 6dB improvement in total harmonic distortion, and a noise floor 2.5dB lower than in their last-generation hardware.

Devialet’s AIR app worked well, operating invisibly in the background as I streamed content -- I could use iTunes, Roon, and Tidal’s dedicated applications on my MacBook Pro, connected to my network via Wi-Fi, with little latency and, more important, zero dropouts. But I found that I had to wire the Expert 130 Pro directly to my network. While AIR was able to find my network wirelessly, activating the Devialet’s Wi-Fi input resulted in an intermittent and super-annoying soft-clipping sound, through the Wi-Fi input itself as well as through all of the other digital inputs. Moreover, despite having a fairly robust home network, I experienced fairly frequent dropouts when the Devialet was wirelessly connected to it. A quick search on the Internet indicated that this may have to do with my Apple network equipment, but I was unable to verify this. Deactivating the Wi-Fi input and using Ethernet proved to be a bulletproof solution.

Devialet’s party trick is their Speaker Active Matching (SAM) functionality. Harnessing the Expert’s powerful DSP software, users can select from one of 725 loudspeaker profiles (at time of writing) from a wide variety of brands, for which Devialet has created an electrical and mechanical profile. With SAM inactive, an Expert 130, like any other amplifier, is agnostic to whatever loudspeaker it’s connected to, and so can’t tailor its output to maximize the bass output or ameliorate potential phase problems. For speakers like my KEF R700s and LS50s, for each of which Devialet has a profile, SAM provides a twofold benefit below 150Hz (SAM doesn’t operate above that frequency). With SAM active on the Expert 130 Pro, the amplifier can predict the electrical behavior of a woofer (or, in the case of the LS50, a midrange-woofer), and tailor its output to almost entirely eliminate the phase issues inherent to any passive loudspeaker. Moreover, since a SAM profile can account for maximal driver excursion, the Expert 130 can dynamically alter a speaker’s functional frequency response. In the case of my KEF R700 towers, at low volumes, when driver excursions are minimal, the Devialet can force the speakers to reproduce lower frequencies than they otherwise would, thus maximizing the available excursional bandwidth. As the volume level is increased, the amp protects the speakers by ensuring that driver excursions don’t exceed a predetermined threshold. Practically speaking, activating the SAM profile for my KEF towers permitted nearly full-range bass reproduction down to almost 20Hz at reasonable listening levels, and ensured that I wouldn’t blow them to pieces if I ratcheted up the volume.

Then there’s Record Active Matching (RAM). Hooking up a turntable to the Devialet is easy via its configurable inputs, and RAM offers 13 equalization curves, giving you the ability to match a curve to whatever EQ was used to master a particular LP. While Devialet’s efforts to remain true to vinyl source material are laudable, keep in mind that every incoming analog signal is funneled through the amp’s analog-to-digital converter, to become a 24/192 digital signal, and then back to analog at the output stage. But I’m not a vinyl guy, so I can’t say anything about the Expert 130 Pro’s phono performance.

Like those of the 120 before it, the Expert 130 Pro’s specifications promise near-state-of-the-art performance. It delivers 130Wpc into 6 ohms, roughly 100Wpc into 8 ohms, or 200Wpc into 4 ohms, and remains stable into loads as low as 2 ohms. Its signal/noise ratio of 130dB -- for the entire circuit, not just the DAC -- is so low as to be scarcely believable. The 130 Pro’s total harmonic distortion plus noise at its full rated power of 130Wpc into 6 ohms is 0.0005% or -106dB -- half that of the 120. And at 10Wpc into 6 ohms, a much more common power level for most users, the THD+N drops to 0.00025% or -112dB. The Expert 130 Pro’s output impedance is 0.001 ohm, which means that it should provide consistent performance regardless of load. And its damping factor of 8000 is sky-high.

Setup

The Expert 130 Pro comes in a stylish black box with a magnetic latch, and with thoughtful accoutrements: a pair of white gloves, to ensure that you don’t sully its mirror finish; the SD card, for customizing the functionality of amp and remote; and that AudioQuest power cord.

I plugged the SD card into my MacBook Pro and, using Devialet’s online configurator, was able to deactivate all of the Expert 130 Pro’s connections other than the S/PDIF optical, USB, and Ethernet inputs. I also selected the appropriate SAM profiles for my KEF LS50 and R700 speakers (SAM can be adjusted or defeated on the fly). I saved the results to the SD card, inserted the card in the 130 Pro, powered the unit up, and away I went.

In addition to the KEF models, I made prolific use of Monitor Audio’s Silver 10 floorstanding speakers, for which Devialet did not have a SAM profile. Speaker cables included DH Labs’ Q-10 Signature and Dynamique Audio’s Caparo. When connecting my laptop to the Expert 130 via USB, I used a DH Labs Silversonic USB link. The Ethernet cable connecting the Devialet to my network was generic, as was the optical cable wiring it to my TV.

Devialet Expert 130 Pro

The Expert 130 Pro functioned almost perfectly. Its dialed remote was a pleasure to use, the unit itself ran only warm to the touch (the 120 runs quite hot), and I could hear barely any white noise from my speakers, even when I practically laid an ear against a tweeter -- the 130 Pro’s noise floor was extremely low. Devialet’s iOS app also worked well, letting me turn the 130 Pro off and on, adjust the volume, and change inputs with ease. Beyond the noise associated with the Wi-Fi input, the only troubles I had were several times when, without warning, the volume ramped quickly up or down, making me jump for the remote to turn it down. This happened not only when I watched TV through the optical input, but when I listened to music through the Ethernet input. Touchy remote?

Listening

I didn’t need to listen to my review sample for very long to hear that the hallmarks of the Expert 130 Pro’s sound were a staggering timbral purity and an utter lack of distortional artifacts. Listening to any decently recorded human voice did the trick, particularly “Cleopatra (Acoustic Demo),” from the deluxe edition of the Lumineers’ Cleopatra (16-bit/44.1kHz FLAC, Dine Alone). Wesley Schultz’s unfiltered, unprocessed voice was shockingly vibrant, hanging in mid-air slightly to left of center. I heard detail by the bagful, and, more important, an organic color and weight that elude even the finest class-AB amps I’ve heard.

It’s one thing to accurately convey musical information -- many amplifiers do it without difficulty. It’s quite another to do so in a way that fools ears and mind into thinking that what’s heard might actually be real, and it was here that the Devialet distanced itself from the competition. It seemed I could hear all the way to the back of the recording studio, and because of this Schultz had a three-dimensional aural presence in my room -- this was no 2D facsimile. And he sounded genuinely natural, his aching, smoky voice fleshed out without sounding bloated. As he reached into his upper register, his voice didn’t go hard or sound in any way tipped up. Nor did I hear anything remotely clinical in the 130 Pro’s performance. I found myself immediately seduced by the Devialet’s complete lack of grain and noise.

Part of what made the Devialet such a persuasive musical conduit was its abyssal noise floor, which allowed recording venues to be “illuminated” in complete and holistic fashion. There was neither spotlighting of musicians at center stage nor veiling of what went on to left or right of them. Combined with a dead-neutral tonal balance that didn’t emphasize the lower and mid-treble -- an easy way to make a recording venue sound bigger than it is -- the Expert 130 Pro threw soundstages that were enormously wide and deep and completely coherent.

In “Air,” from Hans Zimmer’s ruminative score for Terrence Malick’s film The Thin Red Line (16/44.1 FLAC, RCA Victor), large Japanese taiko drums are struck in what sounds like a huge warehouse. The modestly sized Devialet sounded like a figurative hammer on this track -- my KEF R700s not only re-created the sound of these big drums with alarming power and control, but their reverberations seemed boundless. The wooden shakuhachi flute that enters shortly after several drum salvoes was delightfully articulated -- I could effectively hear the player’s breath traveling down the flute’s bore. Spine-tingling stuff.

Devialet Expert 130 Pro

Another defining characteristic of the Expert 130 Pro was its sublime bass performance. In my time I’ve heard a couple of burly amps -- Gryphon Audio’s Diablo 300 and Musical Fidelity’s M6 500i -- that boasted at least 300Wpc into 8 ohms, huge power supplies, and a borderline-irresponsible amount of current capacity. Each produced effortlessly deep, powerful bass -- and yet the Devialet, more like a fencer than a bareknuckle brawler, produced the most satisfying bass response I’ve ever heard. It wasn’t so much that the Expert 130 Pro dug deeper or struck harder -- it was more a matter of unflappable control, and of a particularly masterful precision from 100Hz down.

In “The Game Has Changed,” from Daft Punk’s soundtrack for Tron: Legacy (16/44.1 FLAC, EMI Catalogue), the synthesized bass line strikes early and often. This is genuine midbass that demands a speaker capable of delivering at full voice down to at least 40Hz. With my KEF R700s and their two 6.5” woofers per speaker in my narrow listening room, I expected to hear fixtures rattle -- not the incredible bass impact the Devialet summoned. The amp’s ability to halt my KEFs’ woofers on a moment’s notice was remarkable. This is the kind of controlled power I expect from a pair of DSP-driven subwoofers, not slender floorstanders.

Switching in SAM had a fascinating effect on “The Game Has Changed.” Activating SAM turns on the Devialet’s low-frequency phase correction, giving the user the ability to ratchet SAM’s bass boost from 0% to 100%. When I selected 0% with my two-way KEF LS50s, Daft Punk’s bass line sounded nearly the same as when SAM was turned off. I thought I could hear a touch more detail, and perhaps a slightly less smeared, indolent bottom end, but the difference was very subtle.

Turning SAM up to 25% wasn’t subtle at all. With my speakers’ close proximity to the room’s front wall, this level worked well. At low to medium volumes, I heard greater bass extension, and these minimonitors now even dropped hints of proper bass weight. I was concerned with how violently the LS50s’ midrange-woofers flapped in and out, but their sound remained composed. As I turned the volume even higher, I could hear the bottom end begin to shelve as the Devialet worked to protect my KEFs. Clever stuff.

With the KEF R700 towers offering far-more-potent bass extension, I heard the same highly impressive low-end impact as before, but now with greater reach into the nether regions. The difference didn’t sound in any way forced or artificial, which surprised me. SAM is no mere gimmick -- it can tailor a Devialet amp to maximize your speakers’ potential. I can get behind that.

A word on the Expert 130 Pro’s imaging: Its supremely revealing sound didn’t announce itself with, say, a too-lively top end that lent a specious glimmer to nearly every track. No, it shone through as voices and instruments placed on soundstages with unusual precision. I found it consummately easy to “see,” spread before me, complex arrays of performers -- the word holographic springs to mind. Even great amps, however factually correct, and however well they convey all the detail, pomp, and circumstance you’d ever want, can fail to be musically, emotionally convincing. But the Devialet Expert 130 Pro’s sensational imaging contributed to my engagement with and enjoyment of music to a degree I’ve rarely experienced. Hearing Ben Gibbard’s voice in “Passenger Seat,” from Death Cab for Cutie’s Transatlanticism (16/44.1 FLAC, Barsuk 32), transported me back 11 years and several hundred miles, to a sleepy college town in Ohio. Which is the whole point of this crazy hobby of ours.

Comparison

I didn’t have Devialet’s older 120 on hand to compare with the Expert 130 Pro, but I did have a second-hand Devialet Expert 200. Other than the Expert 200’s power rating of 200Wpc into 6 ohms and a couple of extra inputs, it’s externally identical to the 120.

And to my ears, the Expert 200 sounded almost identical to the Expert 130 Pro -- it was every bit as transparent and resolving, and its power and precision through the bass equaled the new amp’s. Further, the sensational soundstaging and imaging that I remember from reviewing the 120, and that were continued in the 130 Pro, were equally present in the sound of my well-traveled Expert 200.

The only difference -- a subtle one -- was that the 200 seemed to have a touch of upper-midrange/lower-treble prominence that the 130 Pro did not. I heard this most easily in high-pitched women’s voices, as in the opening few minutes of “Mer Girl,” from Madonna’s Ray of Light (16/44.1 FLAC, Warner Bros.). Through the Expert 200, the Material Girl’s closely miked, highly articulate singing included lispier sibilants and a modest emphasis of her highest notes, demonstrating the Expert 200’s lighter, airier interpretation of the track. Through the Expert 130 Pro, by contrast, Madonna’s voice had slightly more weight and heartiness through the diaphragm, with a bit less of that airy quality. I think that the Expert 130 Pro’s timbral balance was slightly more accurate, but otherwise, the two Devialets sounded the same.

Comparing the Expert 130 Pro to my reference Hegel Music Systems H360 was fascinating. I think the Hegel is one of the best DAC-integrateds available. It offers 250Wpc into 8 ohms or 420Wpc into 4 ohms, as well as the expected assortment of analog and digital inputs and outputs, including Apple AirPlay and DLNA functionality via Ethernet. It has no clever apps or software, and its class-AB amplifier is a blunt instrument compared to the Devialet’s chic ADH circuit -- but for $5700, the H360 is about as good as it gets.

Through the H360, Madonna in “Mer Girl” sounded a bit farther forward on the soundstage, and her voice had a sparkling quality that made her sound more vibrant and exciting. The H360’s soundstage couldn’t quite match the Expert 130 Pro in width or depth, and the sporadic bass synth wasn’t as taut or impactful. Moreover, the image of Madonna’s voice wasn’t quite as well defined or holographic. By most every metric, the Devialet’s sound was more accurate. Throw in SAM, AIR, RAM, a killer remote control, and upgradability via future firmware updates (via the SD card slot), and, despite its power deficit, the Devialet is a flaming bargain. And yet, with many tracks, I preferred the sound of the Hegel. With its lively midrange and ability to “pop,” it excited me more -- despite my “knowing” that it was the inferior tool for the job. Maybe, deep down, we all like to be lied to a little. But rest assured -- if I ever left the House of Hegel, my next stop would be the Domicile of Devialet.

Conclusion

With the Expert 130 Pro, Devialet has continued to build on the most excellent foundation of past successes like the 120 and Expert 200. Despite my apathy for such monikers as ADH and Magic Wire, their clever circuits continue to set the bar for audio realism. The Expert 130 Pro’s bass reproduction is preposterously good, and its nonexistent noise floor and extraordinary transparency permit deep inspection of the nooks and crannies of my music. Although $7690 isn’t cheap, I know of many well-respected brands that charge far more and deliver a lot less. My intermittent volume-control problem and questions about wireless AIR functionality remain, but they’re the only blemishes on the record of this otherwise state-of-the-art DAC-integrated amplifier.

. . . Hans Wetzel
hansw@soundstagenetwork.com

Associated Equipment

  • Speakers -- KEF LS50 and R700, Monitor Audio Silver 10
  • Earphones and headphones -- NAD Viso HP50, Pryma 01, PSB M4U 4
  • Integrated amplifiers -- Devialet Expert 200, Hegel Music Systems H360, NAD M32 DirectDigital
  • DAC-headphone amplifier -- Oppo Digital HA-2SE
  • Source -- Apple MacBook Pro computer running iTunes, Roon, Tidal
  • Speaker cables -- DH Labs Q-10 Signature, Dynamique Audio Caparo
  • Analog interconnects -- Dynamique Audio Shadow RCA, Nordost Blue Heaven LS XLR
  • USB link -- DH Labs Silversonic
  • Power conditioner -- Emotiva CMX-2

Devialet Expert 130 Pro DAC-Integrated Amplifier
Price: $7690 USD.
Warranty: Five years parts and labor.

Devialet
SAS 10, Place Vendôme
Paris 1ER
France
Phone: (33) 502-155-682

Website: www.devialet.com