Rogue Audio DragoN Power Amplifier

Rogue Audio needs little introduction in TAS. A perennial overachiever, sonically satisfying and sensibly priced, the company has long been associated with tube electronics. But true to its name, the Rogue team has never been absolutist, blinded by loyalty to the almighty valve. Rather than fleeing from an evolving and tech-driven high end, Rogue has embraced changes for the better. This is where Rogue’s DragoN comes in. It stands atop the Rogue line as its most powerful stereo amp. Indeed, at 300Wpc into 8 ohms and 500Wpc into 4 ohms it has enough output to drive the vast majority of loudspeakers with ease. And at a modest $3995 price it should be affordable for most audiophiles.

Not surprisingly, with this much power on tap in a standard-sized chassis, DragoN is a hybrid tube/Class D design. However, the rogues at Rogue emphasize that it’s not “simply a tube circuit placed in front of a Class D output section.” They describe their proprietary “tubeD” circuit topology as one that integrates the tube section (a pair of 12AU7 tubes) into the amplifier’s output stage. Additionally, three massive linear power supplies built around large, high-performance toroidal transformers power the amplifier circuitry, and top-shelf parts mounted on a heavy (two-ounce) copper circuit board are used exclusively throughout.

Outwardly DragoN pares things down to its chunky essentials. Its Spartan looks are set off by a machined aluminum faceplate. Tipping the scale at just under forty pounds, DragoN is a study in solidity and purpose. A low-power standby mode allows critical amplifier sections to remain continuously powered on (if desired), and a slow-start feature allows the tubes to warm up gradually to eliminate turn-on noise and extend tube life. Rogue considers the DragoN an energy-efficient “green” design, in that it requires zero tube-biasing or regular maintenance. The back panel provides plenty of room for either balanced (XLR) or single ended (RCA) inputs, with heavy-duty gold-plated binding posts and an IEC socket for personalizing the power cord. Every DragoN is tested, burned in, and auditioned prior to shipment. It comes with a three-year limited warranty (six months on tubes).

I asked affable Rogue-In-Chief Mark O’Brien about the hybridization of Rogue’s recent designs. He said, “I’m pretty sure we were the first high-end audio company to come out with a tube/Class D hybrid, and that was back in 2011 (when Class D seemed to finally start sounding pretty good). One of the attractions of Class D amplification is that its high efficiency makes for extremely cool operation, as well as a smaller physical package. What this means is that a well-executed design can work in all kinds of systems—from high-performance audio to high-end home theater. Plus, I really liked the idea of shaping the Class D sound using tubes in a hybrid mode. While we were developing this technology, one of the unique technical achievements we came up with was a way to use a tiny amount of feedback to get the Class D modules to test and, even more importantly, to sound like a super-powerful tube amp. The only downside to our early use of Class D was the negative publicity that was often (and rightfully) attached to first-generation designs.

“We initially chose the Hypex modules because I really like their transparent sound as well as their excellent specs and reliability. Their transparency effectively provides us with a blank canvas on which to create our tube portions of the amp. The OEM modules also offer us the opportunity to add much of our own solid-state thinking to the design—to augment the MOSFET output section of the Hypex. The NCore modules were a no-brainer for inclusion in our new DragoN and the entire amp is designed around them. Beside their great sound, these modules are also microprocessor-controlled, which affords all sorts of features in terms of performance and system protection.”

I commenced my listening sessions using the preamp outputs of the superb Aesthetix Mimas integrated (a 2020 Golden Ear Award recipient) to drive the DragoN. The beneficiary of the amps’ output were ATC SCM20SL compacts, the Sonner Audio Legato Unum, and the PSB Alpha T20 loudspeakers. Sources were the Lumin S1 media player with MQA decoding, dCS Puccini disc player (for SACD), and a newly refurbished SOTA Cosmos Eclipse turntable (with vacuum hold-down and SME V tonearm). Cabling was Wireworld Silver Eclipse. Audience and Shunyata provided the line conditioning The ATCs, it should be noted, are speakers with relatively low sensitivity (84dB). They require significant power in order to snap to attention. The DragoN seemed to fit the bill.

Turning to performance, when I open an evaluation of an amplifier like the DragoN I tend to lean in the opposite direction from where some might assume I’d go with 300 watts to burn. Simply put, rather than cueing up a symphony’s most spectacular moments, I elect to get a handle on the amp’s resolving power with smaller stuff. Reproducing micro-dynamics—the tiny transient cues (right down to a squeaky piano bench or the rustle of a soloist’s clothing) that exist just above a venue’s noise floor—is the key qualifier. This is what I want to focus on at the outset of an evaluation. And this was exactly what I got from the DragoN. In this realm, Rogue’s DragoN manifested a level of near-granular finesse and clarity from back-of-the-hall percussion—capturing the snap and rattle of a drum snare, the flutter of a harp, the plink of a harpsichord, or the clap and jingle of a well-struck tambourine. Transient information—a favorite of mine is the soft tick of classical guitarist Michael Newman’s fingernails upon the strings—was naturalistic. Another prime example is solo piano, which this amp reproduced in a full-throated portrayal that ranged from eerie soundboard harmonics to playful presto notes.

In tonal character the DragoN was predominately neutral, with glimmers of midrange warmth and a well-defined presence range. Violin and viola were particularly well-rendered and distinct, with contrasting attacks and decays. The DragoN’s top end was open if not very airy—a minor deduction. Bass response and retrieval were superb, with very good speed and control. Heavy or ponderous? Not at all. In its transient liveliness the DragoN’s personality was lighter—imparting a feel that was, in a sense, optimistic and upbeat. But the voice of authority lurking was always at the ready—to reproduce an organ’s pedal point or the left hand of a pianist striking the bottom-octave keys of a concert grand. The DragoN’s timbral and textural contrasts between instruments was nothing less than exacting. An example I’ve often pointed to is the complex interplay in the “country-style” chamber music of Appalachian Journey, which, if your system is up to it, mingles varying acoustic densities of fiddle, cello, and bass in a raucous musical stew. The ability of a system to track this recording’s immersive qualities and interwoven images can challenge even the best systems

During the “Liberty Fanfare” from Winds of War And Peace [Wilson Audio] the Rogue resolved the full character of lengthy instrumental and acoustic sustains, including the final decay of the immense bass drum, right down to the tactile ripple of its drumhead. This is the sort of fine-grained, eyebrow-raising information that enriches and authenticates a performance.

When it came time to fully open the taps, the DragoN did indeed perform up to fire-breathing expectations. Taking its full measure was the splendid John Williams At The Movies [Reference Recordings]—in this instance the 24-bit/176kHz version running through the Lumin S1 music player. Of the many great tracks on this outstanding disc, it was the rangy cut from The Cowboys, Williams’ Coplandesque film score, that let the DragoN show off its dynamic and rhythmic drive to best effect. From the youthful, galloping exuberance of the main theme to the brassy majesty of the overture’s middle section, DragoN placed the listener squarely in the saddle. This bouncy liveliness was a constant companion during my evaluation, reminding me that the true goal of a high-power amp is to provide enough headroom to bulls-eye transients and unleash dynamics. A big amp is less about sheer SPLs, which are restricted by the transducers and loudspeaker design, and more about giving those drivers the power they ask for in real time and on an instantaneous basis to preserve resolution and avoid distortion and coloration.

The character of the DragoN also inclined me to reconsider old stereotypes of Class AB tubes and solid-state, and Class D. Not long ago these amplifier segments were often fairly easy to define and distinguish. They had recognizable and predictable characters and colorations. Tubes conveyed a romanticized rose-colored warmth, bloom, and dimensionality, with a gentle rounding of resolution at the frequency extremes, a lack of edginess on top, and a softening of bass timbre. Solid-state weighed in with terrific control and low-end dynamics, great extension at the frequency extremes, with perhaps some edge or grain in the upper octaves. And finally Class D had punch, stump-pulling bass extension and control, a dearth of harmonic bloom, and a limited dimensional perspective. As the hours passed listening to the hybrid DragoN, this sort of typecasting virtually went the way of the horse and buggy.

From the outset it became abundantly clear that imaging and dimensionality were heavily on the minds of the Rogue Audio team. The soaring voices of the Turtle Creek Chorale during the Rutter Requiem conveyed both an immersive and layered quality that drew me ever closer to the performance. The DragoN put on a display of spaciousness that I have rarely experienced in tubes or transistors of this caliber. A sense of air movement in the hall, pressurization within the venue, brought Stravinsky’s ever-colorful Pulcinella ballet excerpts to life. Images were portrayed as they are in life, suspended in a warm atmosphere rather than a cold electronic vacuum. And throughout, there was never a whiff of electronic artifacts smearing the ambience around an image.

In the upper reaches of the high end, there are just a handful of glitter-glam companies that seem to inhale most of the air in the room. Most of us know their names. Granted, they’re dazzling, exquisitely engineered, with musicality to burn. However, to my way of thinking Rogue Audio generally, and the DragoN in particular, represents amplification that in its muscular performance and uncommon value should be equally celebrated. Rogue Audio’s contributions have been vastly underrated in my view, and the DragoN provides even further and unassailable evidence. Not just another high-powered beast, the DragoN is a truly splendid piece of electronics that can proudly grace any system.

Specs & Pricing

Power output: 300Wpc into 8 ohms, 500Wpc into 4 ohms
Inputs: Unbalanced on RCA jacks, balanced on XLR jacks
Tube complement: 2x 12AU7
Output stage: Hypex nCore Class D
Input impedance: 200k ohms
Frequency response: 10Hz–20kHz ±1dB
Dimensions: 18″ x 15″ x 5.5″
Weight: 38 lbs.
Price: $3995

ROGUE AUDIO, INC.
PO Box 1076
Brodheadsville, PA 18322
(570) 992-9901
rogueaudio.com