Reviewers' Choice“Have fun dancing with the Devil.”

It’s the sort of line a B-movie bad guy would growl. It’s not the sort of sign-off you expect to see at the end of an e-mail from the founder and CEO of a high-end audio manufacturer. Yet Flemming E. Rasmussen, of Gryphon Audio Designs, in Denmark, had written just that in confirmation of my receipt of his company’s Diablo 300 integrated amplifier. If it were any other manufacturer, I’d have rolled my eyes and moved on. But Gryphon’s creations are bold and unusual looking, and I’d waited a long time to review one. I chuckled. Nervously.

Gryphon Diablo 300

An exercise in expression

Often, it appears that a manufacturer’s primary goal is not to please as many listeners as possible, but to offend the fewest. I get it -- it’s good business. It also leads to a landscape littered with boring boxes of wood and metal, few of which exhibit any real personality -- soulless constructions devoid of discernible emotive qualities. And for most people, that works.

The Diablo 300, Gryphon’s flagship integrated amplifier (€12,800; €17,600 as reviewed, including DAC module) is not boring. It weighs 84 pounds, and it’s big -- 18.9”W x 9.2”H x 18.1”D -- a hulking mass of anodized black aluminum, heatsinks, and squared edges. With its only curves being its feet and its rear-panel connectors, the Diablo looks more like something created in Tolkien’s Mordor than in Denmark, officially the world’s happiest nation. When I set it up in our living room, my better half was aghast. I confess that, deep down, her response gave me just the slightest bit of pleasure. Which is sort of the point, I think. The Diablo 300’s brutalist aesthetic may not be pretty, but it sure is provocative.

Gryphon Diablo 300

An overhead view of the Diablo reveals bolts on the sides that are larger than the ones at the front. So, too, with the massive heatsinks that form the amp’s corner edges and run from front to back, and are of a bigger gauge than the sink that runs from top to bottom of the center of the front panel. The Diablo is oddly proportioned: its structural frame sits higher than the slightly recessed and partially vented top panel, the tops of the heatsinks sitting lower still. Laser-etched into the top panel, in large caps, is “THE GRYPHON”; below that is an image of the mythical creature. The Diablo has the visual personality of a benevolent dictator: It doesn’t need to be loved, just respected.

Given all that, you might assume that the Diablo 300 has a raw, unpolished, deal-with-it build quality. That couldn’t be further from the truth. Handmade by Gryphon in Denmark, the Diablo is solid -- outstanding attention has been paid to craftsmanship and materials. The front panel of machined acrylic has a semigloss coating that offsets the matte finish of the top and side panels of aluminum. The trapezoidal, capacitive, vacuum-fluorescent display is a delight, with easy, responsive operation that results in the satisfying clicks of mechanical relays in action. Even the connections at the rear feel special, with oversize binding posts the likes of which I’d never seen before, and an array of gold-plated balanced and unbalanced inputs. Gryphon’s flagship integrated is, if nothing else, utterly authentic.

The Diablo 300 is also a hammer of an amp, generating more power than anyone should ever need: 300 or 600 or 950Wpc into, respectively, 8 or 4 or 2 ohms. Its stability into 2 ohms while generating almost 1kW of power is particularly impressive. While the Diablo’s circuit is nominally class-AB, it’s highly biased, operating in class-A mode for the first 10W or so. The dual-mono, zero-negative-feedback design has a sizable power supply that provides 136,000μF of capacitance, and has two- and four-layer printed circuit boards. Gryphon claims for the Diablo an ultrawide frequency response of 0.1Hz-350kHz, -3dB; an output impedance of 0.019 ohm, which suggests highly consistent performance even into challenging loudspeaker loads; and less than 0.1% THD+noise (no associated power rating specified).

Gryphon Diablo 300

Out back are those huge binding posts, as well as two balanced (XLR) inputs, three unbalanced (RCA) inputs, dedicated subwoofer and tape outputs, an AC fuse, a ground post, an IEC power inlet, and multiple 3.5mm trigger connections. The upper, central part of the rear panel is occupied by a blocked bay, labeled Optional Module, for a digital-to-analog converter (€4800) based on Gryphon’s respected Kalliope DAC, and/or a moving-magnet/moving-coil phono stage (€1800). These can be installed at the factory or by a dealer.

I’m an all-digital guy, so I asked that my review sample be fitted with the DAC module, which features the well-regarded ESS Sabre ES9018 chipset (the Kalliope uses two ES9018s in a dual-differential circuit) and asynchronous USB, AES/EBU, optical, and dual S/PDIF coaxial connections. The USB input accepts signals of resolutions up to 32-bit/384kHz PCM and DSD512; the remaining inputs are limited to 24/192 PCM signals. Also, decoding of DSD256 and DSD512 signals via USB is possible only with Windows computers; devices running an Apple or Linux OS max out at DSD128. Gryphon’s DAC module permits the use of selectable PCM and DSD filters via the Diablo’s menu system. Slow rolloff (short group delay) and sharp rolloff (long group delay) digital filters are available on the PCM side, while the DSD side has a first-order, analog filter that can be left off or set for 50, 60, or 70kHz (50kHz is the default). I didn’t explore these filters too much. A quick comparison pointed me to the slow-rolloff PCM filter, which sounded a touch more natural and concise, which is just as well -- it’s the Diablo’s default setting.

Gryphon Diablo 300

Finally, the remote control. No slave to convention, Gryphon has opted for a long aluminum box with square cross section in the same satin black as the Diablo’s side panels. At one end is a built-in stand that lifts and tilts the remote to face the user. At the other end is the Gryphon logo in white. This quirky-looking device was a pleasure to use, mostly because of its clicky, responsive aluminum buttons.


The Diablo 300 arrived in a massive crate that collapses on all sides to make moving the beast as easy as it can be. Because I’m irresponsible and antisocial, I wound up moving the Gryphon into my system without assistance -- asking for help wouldn’t have been a bad idea. The included white gloves kept me from besmirching the Diablo’s perfect, satin-black finish.

Setup was a breeze -- the substantial binding posts were a pleasure to use, while the USB and optical inputs, respectively connected to my old Apple MacBook Pro laptop and TV, worked instantly. I used Dynamique Audio Caparo speaker cables, a Nordost Blue Heaven USB cable, and Nordost’s Blue Heaven power cord plugged into an Emotiva CMX-2 power conditioner. The Diablo is a plug’n’play, one-box solution. The reasonably intuitive menu system made operating the Diablo a breeze.

I used a variety of loudspeakers with the Diablo 300 during its four-month stay: my own Monitor Audio Silver 10s and KEF LS50s, as well as review samples of Magico’s S1 Mk.II and Sonus Faber’s Venere S. I compared the Diablo 300 to my reference Hegel Music Systems H360 DAC-integrated, while also making use of a T+A Elektroakustik MP 2000 R DAC-network client to evaluate the Gryphon’s optional DAC module.


I expected Gryphon’s übermasculine he-amp to sound boorish and something of a lout, with punctuated highs and overemphatic bass. But the Diablo 300 had all the grace and finesse of a ballet dancer. Like a Navy Seal who joins a seniors’ book club, or a lumberjack addicted to yoga, the incongruity was almost risible. That’s not to say that the demonic Dane was too kind to recordings. No, Gryphon’s flagship integrated expressed itself quite comfortably.

In the past two years I’ve been exposed to a variety of integrated-amplifier circuit designs, including Devialet’s hybrid class-A/D 120, Luxman’s class-A L-550AX, Octave Audio’s tubed class-A/B V 110, and multiple solid-state class-AB models. I’ve come to the conclusion that while class-AB integrateds, like my reference Hegel H360, offer a terrific combination of thermal efficiency, power, and performance, they can’t convincingly re-create the magic of a live musical performance. I could never put my finger on that magic while listening to my Hegel, but swapping the H360 out for the Diablo 300 instantly reminded me of what I’d been missing. The Gryphon may consume 200W at idle, and almost ten times that at maximum output, while also serving as a space heater (it put out a fair bit of heat), but energy bill be damned -- it sounded magnificent.

Gryphon Diablo 300

In evaluating the sound of an audio component, I often begin with the human voice, to establish a baseline for the product’s tonality, imaging, and resolution. The Gryphon allowed me to hear that any tether between Magico’s S1s and Art Garfunkel’s voice in the title track of Simon & Garfunkel’s Bridge Over Troubled Water (16-bit/44.1kHz ALAC, Columbia) had been dramatically loosened: His voice seemed to occupy a firmer, more clearly defined point in space between the speakers, resulting in a more holographic reproduction. Moreover, Garfunkel’s voice took on a sweeter, more golden quality. This didn’t sound like an outright tonal coloration, but simply greater bloom and vivacity than I’m used to hearing. It was delightful to hear one of my favorite songs reproduced with such a full-bodied midrange. Even the quite audible noise floor of this recording, and the cymbals that appear halfway through the track, took on an organic feel that helped bridge the gap between the electrical and mechanical reproduction of music and the real thing.

The Diablo 300 reproduced the opening kick drums of “Dreams,” the first single from Beck’s as-yet-unnamed next album (16/44.1 FLAC, Virgin), with hearty weight: full but not fulsome. The guitar in this track has a raw, distorted edge that could well teeter toward brightness, but the Diablo’s dulcet top end seemed to rein this in for the occasional stanza-ending riff. Its treble response was as extended as that of any other amp I’ve recently reviewed, but was also incredibly smooth -- overall, the top end was less lively and spacious than I expected it to be. There was no hint of zing or sparkle, just effortless extension.

Gryphon Diablo 300

The more intimate “Fool,” from Børns’s Dopamine (16/44.1 FLAC, Interscope), seemed to pop from between my Monitor Audio Silver 10s with purpose and alacrity, again exhibiting a kind of spooky detachment from the speakers. Garret Borns tends to sing at the upper end of the male register, and this, combined with his light, delicate tone, at first made me think that he was a she. Through the Diablo 300, I could easily make out Borns’s closeness to the vocal mike at the beginning of “Fool,” which gives his voice a crooning, wafting feel. In the chorus, Borns seems to lean back as his voice goes even higher, and seems to be farther away on the soundstage -- the beautiful result is a deeply compelling sense of soundstage depth. Due to the smallish, nearfield setup of my listening seat -- my speakers are about a foot from the front wall of my medium-size room -- it’s rare for me to hear appreciable and convincing soundstage depth. With the Gryphon, I could.

Ramin Djawadi’s “Light of the Seven” is the haunting accompaniment to the first ten minutes of the final episode of Season 6 of HBO’s Game of Thrones (16/44.1 FLAC, Varèse Sarabande). When, during the original broadcast, I heard it through the Gryphon, I was struck by how deliberate the tempo was -- at odds with a television show that is anything but subtle. The opening features a piano and a handful of strings. A single viola appears in the left channel, as the piano dominates the center of the soundstage. As I listened to this piece again, I immediately noted the rich texture of each instrument. The viola took on a dense, sorrowful tone, while the hammers-on-strings action of the piano sounded almost velvety. Some of this is due to the mastering of the track -- it’s certainly not intended to be airy and light -- but a small portion of it was also attributable to the Diablo. I sometimes find that this sort of substantial articulation of the midrange comes at the expense of masking fine detail, but it didn’t with the Diablo. I could have my cake and eat it, too. These are fine margins that the Gryphon managed to artfully navigate.

Gryphon Diablo 300

To test the Diablo 300’s optional DAC module, I played a high-resolution version of “Ubi Caritas,” from Ola Gjeilo’s Piano Improvisations (DSD64, 2L), first through the Gryphon, then through T+A’s MP 2000 R ($8500). The differences were more obvious than I thought they’d be. Gjeilo’s piano felt more plush and voluminous through the Gryphon DAC; tonal colors were more intense, and the instrument felt more dense and solid. Through the T+A, the piano sounded lighter, airier -- as if the MP 2000 R were putting more emphasis on the higher harmonics of a high note, which gave it a leaner, more light-on-its-feet sound. The T+A DAC-streamer seemed to be more resolving, but at a cost: a little upper-midrange hardness. The Diablo 300’s DAC module wasn’t quite neutral through the midrange -- high-quality external DACs may better it in the reproduction of the finest details. That said, at least a small portion of the Gryphon’s magical midrange and silky treble reproduction could be credited to its DAC module. Could a Diablo 300 buyer do better? Probably. But not by much.


It’s been too long since I’ve heard Devialet’s 120 DAC-integrated for me to try to meaningfully compare what I recall of its sound with that of the Diablo 300. (The newest version of the 120, the 130 Pro, costs $7690.) At the time, I felt that it was the best piece of integrated electronics I’d ever heard. In terms of overall sound quality, the Gryphon plays in the same ballpark.

But I’m not sure that matters. Someone shopping for a reference-level integrated amplifier might be looking to jump up from something like my Hegel H360 ($5700). The question might be, “Just how much better can something like the Diablo 300 be?” Despite being roughly half the height and weight of the Gryphon, the Hegel puts out 250 or 420Wpc into 8 or 4 ohms, respectively. That may not be up to the level of the boulder-crushing Gryphon, but odds are it’s more than enough for most audiophiles. Additionally, the H360 has an excellent onboard DAC, a next-generation class-AB amplifier with built-in error correction, and a secondary power supply for its preamp and digital circuitry.

Gryphon Diablo 300

But despite how accomplished the Hegel is for its relatively modest price, in many ways the Diablo 300 is just better. The H360’s simple, folded-metal case is child’s play compared to the Diablo 300’s overbuilt, military-grade armor. There’s also the Diablo’s pomp and circumstance. The Gryphon’s appearance has a sense of occasion; the Hegel merely looks like a nice piece of electronics.

But it’s the sound that counts. Compared to the Gryphon, the Hegel sounds flatter, more compressed. The Diablo was also far more quiet. While both are highly resolving, I could consistently hear a smidge more through the Diablo 300. Further, the Hegel’s ultraclean, ultrasmooth sound differed from the Gryphon’s, which was sweeter and more robust. The biggest difference between the two was the level of engagement with the music that I enjoyed. The Gryphon was a big step up from the Hegel in its musicality and realism. With the H360 in my system, especially through Magico’s top-shelf S1 Mk.II speakers, I felt I was listening to a very high level of reproduction of music. But with the Diablo 300 driving the Magicos, my experience of music was more transcendent, pushed the envelope more; in a word, it sounded more real. The Hegel is excellent for the money. The Gryphon is excellent, period.


Gryphon Audio Designs’ Diablo 300 is a unique audio component. Its visual or electronic design is unlike that of any other high-end component I’ve seen, and its build quality is exceptional. The Diablo 300 is designed to easily corral any speaker on the market -- it never broke a sweat, even when I presented it with a challenging load and pushed it hard. Its sound quality is of high caliber -- it delivered some of the most involving and convincing reproductions of music I’ve ever heard in my listening room, with a sound marked by a golden midrange and sweetly extended highs. Add to this its ostensibly unlimited reserves of power, and it’s apparent that this integrated amplifier shouldn’t be thought of as a step in a journey, but as the final destination. Its bold styling won’t appeal to everyone -- but for those who can’t look away, nothing else will do. The Diablo 300 is a mad, inimitable masterpiece.

. . . Hans Wetzel

Associated Equipment

  • Speakers -- KEF LS50, Magico S1 Mk.II, Monitor Audio Silver 10, Sonus Faber Venere S
  • Earphones and headphones -- NAD Viso HP50, Pryma 01, PSB M4U 4
  • Integrated amplifiers -- Hegel Music Systems H360, T+A Elektroakustik PA 2000 R
  • Digital-to-analog converters -- Arcam irDAC, T+A Elektroakustik MP 2000 R
  • Source -- Apple MacBook Pro running iTunes and Audirvana Plus
  • Speaker cables -- DH Labs Q-10 Signature, Dynamique Audio Caparo
  • Analog interconnects -- Dynamique Audio Shadow (RCA), Nordost Blue Heaven LS (XLR)
  • USB cables -- DH Labs Silversonic, Nordost Blue Heaven
  • Power conditioner -- Emotiva CMX-2

Gryphon Audio Designs Diablo 300 DAC-Integrated Amplifier
Price: €17,600 (€12,800 without DAC module; add €1800 for MM/MC phono module).
Warranty: Three years parts and labor.

Gryphon Audio Designs
Industrivej 9
8680 Ry
Phone: (45) 86891200
Fax: (45) 86891277