Reviewer: Srajan Ebaen
Financial interests: click here
Sources: Retina 5K 27" iMac (4GHz quad-core with Turbo boost, 32GB RAM, 3TB FusionDrive, OSX Yosemite. iTunes 12.2), PureMusic 2.04, Qobuz Hifi, Tidal Hifi, COS Engineering D1, Metrum Hex, AURALiC Vega, Aqua Hifi La Scala MkII, Fore Audio DAISy 1, SOtM dX-USB HD w. super-clock upgrade & mBPS-d2s, Apple iPod Classic 160GB (AIFF), Astell& Kern AK100 modified by Red Wine Audio, Cambridge Audio iD100, Pro-Ject Dock Box S Digital, Pure i20, S.A. Lab Lilt [on loan]
Preamplifier: COS Engineering D1, Nagra Jazz, Esoteric C-03, Bent Audio Tap-X, Vinnie Rossi LIO
Power & integrated amplifiers: Pass Labs XA30.8, FirstWatt S1, F6; Crayon Audio CFA-1.2; Goldmund Job 225; Gato Audio DIA-250; Aura Note Premier; April Music Stello S100 MkII; Wyred4Sound mINT; AURALiC Merak [on loan]
Loudspeakers: Albedo Audio Aptica; EnigmAcoustics Mythology 1; Sounddeco Sigma2; soundkaos Wave 40; Boenicke Audio W5se; Zu Audio Submission; German Physiks HRS-120, Gallo Strada II w. TR-3D subwoofer; Voxativ 9.87 system [on review]
Headphones: ALO-rewired Sennheiser HD800, Beyerdynamic T1 & T5p, Audeze LCD-2 and LCD-XC, AKG K-702; stock-cabled HifiMan HE-6, HE-560 both with upgraded pads; MrSpeakers Alpha Dog and Alpha Prime; Aëdle VK1; Ortofon eQ5; Hifiman HE1000
Headphone amps: Bakoon AMP-12R, Eximus DP1, Stello HP100MkII, Questyle CMA800R (x2)
Cables: Complete loom of Zu Event MkI and MkII; KingRex uArt double-header USB; Tombo Trøn S/PDIF; van den Hul AES/EBU; AudioQuest Diamond glass-fibre Toslink; Arkana Research XLR/RCA and speaker cables [on loan]
Power delivery: Vibex Granada/Alhambra on all components, 5m cords to amp/s and subwoofer
Equipment rack: Artesania Audio Exoteryc double-wide 3-tier with optional glass shelves and Krion or glass-based Exoteryc stand/s for amp/s
Sundry accessories: Acoustic System resonators
Room: Irregularly shaped 9.5 x 10m open floor plan with additional 2
nd-floor loft; wood-paneled sloping ceiling; parquet flooring; lots of non-parallel surfaces (pictorial tour here)
Review component retail: €5'000

That the URL spells glabdefi.com is surely no coincidence. Who do we think they defy?

G Men. The year was 1935. A Warner Bros. crime film starring James Cagney became one of the top-grossing movies of the year. Unlike Cagney's earlier The Public Enemy which celebrated gangster life, G Men was the first flick to turn tables and make the federal agents the cool heroes of the day. Suddenly teenage boys dreamt of joining the FBI, not the Scarface gang. Now it's 2015 and we have G Lab Design Fidelity from Poland. Their Block integrated amplifier means to make valve amps hip and heroic for the 21st century; and by extension, turn the tables on transistors as the new public enemy #1. Except that as even sales manager Dionizy Konieczny would have to admit, they're way late to this party. Valves have been cool again for decades ever since hifi's retro torch jumped from early Japanese SET'n'horn experimenters to Europe, then to the US. The story's circular arc went from Western Electric in the US to "Eastern Electric" in Japan, then back to the West. What it bridged was the rise of transistors. For most intents and purposes, transistors displaced vacuum tubes in hifi and elsewhere even though the Soviet military held on and kept developing tube technology. The small Gallic village in the Asterix comics is surrounded by the Roman empire and relies on a miracle drug to keep its resistance afloat. Just so there remained small thermionic holdouts within the dominant solid-state empire. In Europe it was Jean Hiraga who spearheaded the resurgence of glowing glass. In charge of reseeding the American colonies was the New York Triode Mafia around Don Garber's legendary Fi shop and its various acolytes. Their miracle drug was rediscovering direct-heated triodes like the PX25, 2A3, 45 and 300B. By now all that's ancient history. So is the fact that some of the most outrageously styled amplifiers can run valves. If that's a good thing, you could argue that one can never have enough.


Ka'chinnng. With a hifi brand name ending in Design Fidelity, we knew even before looking that the Block would play up its industrial design. In that and its Polish origins, it's not all that unique. The Eggshell amplifiers from Encore 7 too celebrate a marriage of tubes and snazzy threads [sample with round remote at right]. With just 5.5wpc, today's Block is no big-block engine. This led me to repeatedly stall their review solicitations until with Holger Adler's Voxativ 9.87 system, I'd finally have 99dB speakers on hand to properly exploit such a flea power proposition. Going loud enough is far from synonymous with sounding brilliant. For brilliant SET sound, the right load is mandatory. For one, it runs the tubes in their most linear operating region. To even come close to realizing a triode's reputation for most linear gain device made, one must keep its distortion low. With just a handful of watts, that means below one. For two, ambitious woofer schemes with high back EMF tend to prefer higher damping than most SETs generate. As it turns out, the actual people responsible for the Block's manufacture are from Elzab. We're told that they're "a company with over 40 years of tradition in development of mechanics and electronics". Their assistance was vital because designer Mateusz Główka is a Fine Arts graduate, not a Polytechnic alumni with an electrical engineering degree. The G Lab brand is actually owned by Comp Innovation Center Ltd who also own Elzab. Comp's executive director Julian Kozankiewicz came up with the notion of launching this amplifier project after learning of Mateusz Główka's concept design in Wired magazine. Current sales manager and DJ Dionizy Konieczny is our third G Man.


Cynics might opt out now. They'll argue that their Block couldn't be more than a fancy design exercise in pen and paper that was made manifest in metal and glass using ancient textbook circuits and off-the-rack iron. Wearing my own cynical hat, that's exactly what my review would have to investigate. A Google search on Elzab arrives at a company which specialize "in the production/distribution of a wide range of cash registers, devices and systems for points of sales, peripherals and accessories for sales registering and managing". Whilst that's no different than the cash-register HCP doo parent company behind Serbia's Auris Audio tube brand, it does beg the obvious question. Just what do cash registers and their designers know of advanced tube electronics and specialized output transformers?

It takes no listening or wondering, just one glance at our federale to know of its single-ended heart. There's only one EL34 per channel. Power consumption confirms necessary class A bias. To deliver 5.5 watts into the loudspeaker, the stainless-steel Block draws 120 watts from the wall. In fact it'll do that at idle driving nothing. That's far from lime green energy conscious but does come with the territory. Tube cognoscenti have already done the math to realize that these EL34 pentodes are strapped to lower-power triode mode. Unusually, one of the three inputs is for MM phono. That explains the pair of E88C for added gain. The 6N6P dual triodes drive the output tubes and double as line-level inputs. -2dB frequency response is given as 30Hz - 30kHz. DImensions sans bulbs are 339 x 288 x 208mm WxDxH, weight is 20kg. As you've seen, the Block inverts the usual trafos-on-deck scheme by using its four canisters (2 x OPT, 1 x PSU choke) as apparent footers. In reality, the entire affair sits on a central cylinder housing the AC transformer and power supply. Doubling as stand and low centre of gravity, it floats the surrounding quadrant of cubes and supports the signal-path circuitry of the upper deck with its traditionally exposed bottles. It's a clever divide 'n' conquer scheme of clean and dirty boxes. Being foremost a design-centred project, the website follows suit to focus on large professional photos. This sidesteps discussions on circuit and transformer details plus expanded specs. To be sure, such a focus doesn't disavow good sonics. Simple well-proven circuits implemented correctly, then used properly can work very well. They simply don't introduce anything new or advance the art. Not that G Lab claim to do so; or are under any obligation. We're simply curious. Just how would Marian Kopecki in charge of translating Mateusz's optics into electrical engineering describe the Block to audiophiles, not design freaks?