Calling 80mm a sub. As measured across its surround's inner edge, that's all of this mid/woofer's Ø. It's the rubber suspension's additional 25mm width all around with its half-sausage prominence promising disproportionate throw which prevent capsizing this transducer in a sea of ridicule when we call it a subwoofer. Whilst obviously in miniature, it is the appropriate moniker. Like any other proper bass pump, we expect real potential for violence but no final words on refinement or coming on song at midnight levels. Fittingly, under recommended setups on Greg's product page, he lists moderate to high listening volumes. This tracks my quick note that Viper's wakefulness needs more caffeine than specialized whisperers like high-eff widebanders. I'm not talking about flapping my desktop ears like a donkey's in a tornado. I simply mean SPL above what I usually run to hear myself think and get work done. Once we cross this threshold, Viper does the king cobra bit. It lifts itself up on its tail, hood fully flared. Things get really big and depending on what we play, even scary. That's because on a desktop, we anticipate and mostly get miniaturization. We expect not only half or less soundstage width compared to our main system but less LF reach and power. Most of all, we expect a rather lower intensity gradient. Here Viper's appetites are grander. Whilst soundstage width remains limited by speaker placement—a capacious 175cm dust-cap centre to dust-cap centre in my case—and nearby boundaries influence depth, raw intensity was the marker which Viper moved up. In one fell swoop, it did the irrational of shrinking my Qualio IQ by at least 9/10th so they could perch on modest stands whilst transplanting sound of equivalent pedigree. This effect had one primary expression and behind it, one probably primary enabler. Bass coverage for reach and power was stupendous. Hiding in its shadows must have been Viper's internal scales breaking up rear waves to silence 7-litre cabs. Despite the sonic solidifier and densifier action which a firm bass foundation exerts and the blackness that injects into the colour palette, high desktop SPL didn't have Viper get sloppy or poncy. The sound didn't become dirty, bloated or opaque. Whatever SPL Grzegorz invokes in his 40m² studio to overdrive Viper without high-pass protection, I couldn't even imagine – at least not in my office.

A truly hung low end needs a fully liberated top end to maintain balance. Give white and black, air and mass, shine and granite equal presence. Finally hearing my favourite tweeter in the office was a rare treat. Greg really hit upon two ideally matched drivers. In his filter/box implementation, they generate a strongly materialized fleshy chunky sound which completely belies physical dimensions and their typical monitor aesthetic. There's nothing lightweight, wispy or wan about this very atypical small monitor. It's a bona fide heavyweight slugger. That profile naturally prefers an amplifier diet of red meat. To check whether Simon Lee's integrated left crumbs beneath my table, I replaced it with 500-watt Ncore monos [white arrows]. Whilst overall drier and not as sophisticated in the treble, they still had superior control over the reading's 'sub' aspects. Because Viper's native tuning anticipates high negative feedback in switching amps—Laiv's don't fit that mould and instead sound like warm class A—the sound retained attractive tonal fat; not as much as the Korean class AB amp but the feel of overall pace picked up. So did separation. Even curtain lift happened sooner on the volume dial. Because I fancy those aspects, I stuck with the Ncore monos. My high-power class AB amps don't fit the size constraints of my desktop. Good thing a little voice in my head had insisted that the Nord amps weren't part of my recent spring cleaning. And, I'll still play the 'organic' and 'rich' cards when paraphrasing Viper's voicing coming off amps whose overly controlled dryness usually sees them side-lined. Unlike most self assessments for taxes, Greg's assessment of Viper preferring high-power dry class D is honest. As the easiest way to secure high power of low Ω which is what Viper's inefficiency and driver type want, he set his tuning like a chef tailors his starter, desert and recommended wine to an entrée. We can always order off-menu. But if the boss in the kitchen is good and not just an egomaniac, trusting him is best. If you pursue Viper, aim at affordable class D to go with. It's really what this speaker was designed around. If you prefer expensive class D like AGD or Merrill, have at it. It's just not necessary to make Viper sing already. That's a true bonus. Your audiophile cred may not think so; your accountant very much will!

A stickler accountant's honesty has its audiophile equivalent in amplitude linearity. Viper isn't completely honest so not flat-lined linear like it might be after a long fast. Our reptile's last meal is still visible in a small upper mid-bass bulge. Less ambitious monitors move that higher to disguise their lack beneath. Being well good past 40Hz, Viper needs no such disguise. It simply cooks the power region of a kickdrum. That flows directly into the aforementioned overall intensity. It has some locomotive quality. It also looks at the meatpacking district. It's the origin of chunkiness. Why this tuning doesn't go sticky like black molasses as long as our amp exerts the required control is down or rather, up to Mundorf's high-output tweeter. It moves four times as much air as a ubiquitous dome tweeter. That becomes the restorative force for any low-down extra fat like a green salad with balsamic vinegar does for a cream-rich pasta mains. In that sense Viper is more comfort home cooking than 3-star minimalist nosh that leaves us hungry. It's pretty much the antithesis of what we think when hearing the words 'studio monitor'. But the vast majority of us don't run home-based recording studios. Why then would we want mean 'n' lean fault finders? What we should definitely want is grand cinema for soundstaging. For image lock and placement specificity, dipole AMT are absolutely superb. Just then I had three pairs in the house to own the right to that opinion. Viper's narrow cabs whose outers disappear far better as reflectors than smooth-skinned big boxes should certainly do their part to minimize secondary sound sources. Response breaching the bottom octave helps to unearth subtle LF cues which make space feel more tacit and large. So don't misread comfort food to imply an impenetrable wall of sound.

Despite unusually high image density, Viper set up properly knows how to throw an enormous well-differentiated and sorted stage. Such corporeal sound simply speaks less to the inner eye and more to the heart and gut. We marvel at the overall scale and intensity but feel less inclined to go walkabout inside this expansive scenery like eyes-first visual listeners do as spectators and observers. Viper strikes me as being more for feelers than thinkers. But even thinkers can see that a hi-tech 'monocoque' very rigid enclosure without typical glues but with premium drivers, posh filter parts including Duelund hookup wiring, the unconventional high-pass option plus very effective isolation footers add up to one loaded proposition. Small but deadly to all notions of compromise and mediocrity. Where wallet cramps go, consider Storgaard & Vestskov's 5-inch 2-way Frida monitor whose floorstanding 3-driver Gro version I reviewed. Frida sells for €15.5K/pr so about thrice what it would cost to self import Viper to Ireland with 23% VAT; and still more than twice if we bought Viper from a dealer. It's all theory of relativity and uncle Albert's twinkly smile.

Back to bass pumps. Few would equate running a subwoofer to ~5kHz with success. What specializes an LF weapon are its throw and required rigidity. Those mean high mass so that the diaphragm withstands the applied pistonic stress without deformation hence distortion. A dedicated midrange needs nowhere near that excursion or mass. In fact, the lighter its diaphragm, the better it responds to micro voltages. That bodes well for resolution the higher that driver is asked to operate. In short, we're dealing with mutually opposing specializations like using a chain saw to trim a beard. Against these basics it's easy to appreciate Greg's enthusiasm for this unusual Dayton driver. It's a class-crossing multi kulti which manages a most contrarious job description; and does so very well. Whilst its looks suggest more brawn than smarts, once we cater to its higher moving mass and resultant low efficiency with pugilistic power, we overcome expected beast-mode shadows. To be sure, this is not primarily about playing loud enough though it eventually could be. My 50wpc Simon Audio Labs integrated had zero issues with stout desktop SPL. It were in fact lower volumes where upgrading drive by nearly a factor of 10 made the bigger difference. To get the best from this driver wants a firm feisty hand on its leash. Right tool for the job. Once you think about it, it's naught but common sense. By virtually marrying Viper to high power by design, this concept builds in extra grandeur and muscularity like an afterthought. These qualities are what high power does pretty much regardless of load. In 2025, it simply doesn't have to cost a lot. Viper's voicing makes sure of it. Once this page had published, Grzegorz commented: "Yes, I believe this is the magic of an ultralight rigid carbon-fibre cone with a big heavy suspension that damps the cone for a low resonant frequency for great extension. It really is an extremely unusual full-range subwoofer."

Coming from a chap who together with his friend designs and manufactures the widebanders for Cube Audio, that statement has teeth. Juxtapose that experience with this comment that a viewer left under one Darko podcast featuring Viper: "… when used with a subwoofer, I question the use of the Dayton Epique subwoofer. Its BL to Mms ratio of 9.8Tm to 26.6g leads me to suspect its midrange performance to be less than optimal. It would be interesting to see the "8 x stiffer than MDF and 3.4 x stiffer than plywood" 10mm thick 3D-printed pyramidal  PETG structure tech and 80Hz high pass filtration combined with the drivers in Lindemann Audio's Move bookshelf speaker or even Markaudio's new MAOP 11MS driver." Once more, to the naked eye and on specs, the Dayton really does look more beastly than refined. At the ear when properly amplified, it translates rather different. In fact, this driver gets the tonal and dynamic intensity from quick high-power transistors for which widebanders prefer no-feedback valves whilst standing no comparative chance in the bass. As chronicled in my genesis story of Qualio's IQ project, Greg and Marek had in fact started with Markaudio Alpair drivers in a monitor speaker before rejecting them in favour of the final 6" SB Acoustics Satori mid and Mundorf AMT combo atop a ported bass bin with a 9½" woofer. For myself, I've reviewed Lindemann's Move, Move Mini and own the MonAcoustic SuperMon Mini which uses dual Alpairs in isobaric mode. Viper is a serpent of different pyramids.