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 3.02, Qobuz Hifi, Tidal Hifi, Fore Audio DAISY1, COS Engineering D1, Aqua Hifi La Scala MkII, Metrum Hex, AURALiC Vega,
Preamplifier: Nagra Jazz, Esoteric C-03, Vinnie Rossi LIO (AVC module)
Power & integrated amplifiers: Pass Labs XA30.8; FirstWatt SIT1, F6; S.A.Lab Blackbird SE; Crayon Audio CFA-1.2; Goldmund Job 225; Gato Audio DIA-250; Aura Note Premier; Wyred4Sound mINT; AURALiC Merak [on loan]
Loudspeakers: Albedo Audio Aptica; EnigmAcoustics Mythology 1; soundkaos Wave 40; Boenicke Audio W5se; Zu Audio Submission; German Physiks HRS-120, Gallo Strada II w. TR-3D subwoofer; Crystal Cable Minissimo [on review]; soundkaos SK16 [on review]
Cables: Complete loom of Zu Event; KingRex uArt, Zu and LightHarmonic LightSpeed double-header USB cables; Tombo Trøn S/PDIF; van den Hul AES/EBU; AudioQuest Diamond glass-fibre Toslink; Arkana Research XLR/RCA and speaker cables [on loan]; Sablon Audio Petit Corona power cords [on loan]
Power delivery: Vibex Granada/Alhambra on all components, 5m cords to amp/s + sub
Equipment rack: Artesania Audio Exoteryc double-wide 3-tier with optional glass shelves, Exoteryc Krion and glass amp stands [on loan]
Sundry accessories: Acoustic System resonators
Room: Irregularly shaped 9.5 x 10m open floor plan with additional 2nd-floor loft; wood-paneled sloping ceiling; parquet flooring; lots of non-parallel surfaces (pictorial tour here)
Review component retail in Europe: €14'500

Nagra's legacy MPA pyramid was one of their earlier pure transistor amps, albeit styled most unconventionally and as such, relatively short-lived.

Famous branding, managed. With iconic status attained as Nagra undoubtedly have, modernizing one's cosmetics can play havoc with buyer expectations on both dealer/distributor and consumer fronts. How the Fine Sound Group have tackled the often contradictory demands of tradition and renewal is shown at right. There's a McIntosh preamp without green lights or meters; an Audio Research deck with rounded corners, a black display and no frontal handles; and a Wadia with a restyled logo recess. The intent is obvious. Capture the stylistic essence to retain instant recognizability; update looks for 2015 and beyond.

When Nagra Audio's nested existence inside the Kudelski Group flew the coop to go solo, the new owners under the freshly formed Audio Technology Switzerland umbrella faced opportunity to revitalize the brand; and the associated danger of diluting or killing off its essence in the process. If one planned on the latter as Thiel's new owners seem so hell-bent on, it's invariably better to launch an entirely new brand from scratch. Clearly Pascal Maroux and Marguerite Kudelski have no such intentions.

The first product completely conceptualized, designed and built since their acquisition was the HD DAC. Its looks remain true to the established laboratory profile with trademark modulometer. The need for more real estate than the legacy footprint provided was cleverly concealed by moving the two power supplies offboard; and by increasing the main casing's depth without altering its width or height. The change is practically invisible inside an equipment rack. Assembling a classic Nagra stack remains visually unified.

The next project became the monaural HD amps. They finally gave Nagra truly load-invariant muscle amps to drive any speaker ever made. It's something they never had before. A first showing at CES 2015 with Wilson speakers really drove that point home. It was merely logical that this ambitious amp platform would soon spawn smaller models. Today's Classic Amp is the first such offshoot. Twice as powerful as the MSA it replaces, it also kicks off the planned demarcation of Nagra's catalogue into two lines called HD and Classic.

Unlike the Fine Sound group led by relentlessly fêted young celebrity designer Livio Cucuzza, the far more conservative new Swiss managers so far resisted the challenge to stamp a new visual imprimatur on their legacy Nagra cosmetics. By name alone, the Classic range promises no change whatsoever. Whilst the top-end HD models should lend themselves to a suitably respectful makeover, the HD DAC as its first member hadn't broached the subject. That was likely a function of timing. Pascal and Marguerite were still growing their sea legs when that early project got underway. Now one wonders whether that precedent shut doors. Even the breath of fresh naming air of Jazz and Melody preamps has passed. The multi-source power supply became the MPS and there's zero lyricism in the new amplifier names. At Nagra, it's business as usual.

Or is it? A single glance at the Classic Amp shows how the stylish heat sink mohawk of the MSA is no more. Just like banking hair cuts, Nagra wisely opted to slash unnecessary spending. Because it was so extravagantly exposed where it required absolutely flawless finishing, the MSA hood ornament was by far its costliest part. A useless pile of rejects I was shown tells the tale. Yet that fancy styling exercise did absolutely nothing for the sound. Since the Classic Amp is very much about raising the sound bar (it's not just two permanently bridged MSA and in fact closer to a small HD Amp), it internalizes its heat sink. This eliminates a known source of manufacturing frustration.

Whilst it really does nothing for the sound either, the modulometer as that most recognizable Nagra detail stayed. So did the big four-pole rotary on/off switch with the intermediary 'auto' and 'mute' positions. Where the Classic Amp diverges from the legacy recipe is the profile. For one of their compact components, it scales to new heights. As a result, the signature fascia now looks comparatively bare. Yet there's more real estate for the business end. It finally accommodates selectable RCA/XLR inputs. The MSA solo'd its XLR to require a plug adaptor to cinch it. A typical Nagra nicety is the retained selectable 1V/2V input sensitivity; and a stereo/biamp/bridge toggle. Speaker terminals are the superb but spade-only Rhodium Cardas blocks. MPS owners will note the trigger ports. Now the MPS can power up the amp/s.

Once we take a quick history lesson from the MSA, we get at a perfectly open Nagra secret. Nonetheless, it still comes as a shock to many who associate the company exclusively with tubes, hence linear technology. This engineering team from just outside Lausanne are experts at switch-mode power supplies. As Chord and Linn have done for untold years in the UK, Nagra have amassed decades of experience with this energy-efficient power-factor-corrected technology already. As you can see, the MSA had it. Would the more powerful Classic Amp? Unlike its gigantic HD elders, it's still reasonably compact. And some of its new height is taken up by a heat sink ceiling. By necessity of its higher dissipation which supports about double the output power over the model it replaces, that thermal exchanger must amount to twice the mass over what the MSA flaunted. Everything thus pointed at an SMPS for the Classic too.

The next photo shows things belly up, bottom cover removed. Hence we look at the circuitry—it usually hangs sloth-like off the solid bar stock of the top-mounted heat sink—upside down. Once again we see the SMPS boards with their telltale low-turn aircore inductors. But just as there was with the MSA, there's again a relatively compact power toroid. On basic stats, the Classic does 100/200wpc into 8/4Ω and doubles that squarely when bridged to parallel mono with twice the current delivery.

Six big electrolytics make for an obvious difference to the MSA and a sign of nouveaux Nagra code. Their older designs shunned oversize caps but the HD Amp also has them, albeit much larger still.