darTZeel NHB-18NS Preamplifier Reviewed

darTZeel NHB-18NS Preamplifier Reviewed

Not a whole lot of "noise" coming out of Switzerland in terms of audiophile products-unless of course you're ignoring the darTZeel NHB-18NS Preamplfier, which Home Theater Review is not. While it may be a bit on the esoteric side-okay it's waaaay esoteric-its unique sound is truly captivating.

DarZeel-NHB-18-PreampReviewed.gifIt's been made clear to me more than once just how privileged I am to receive the actual production version of the long-awaited darTZeel NHB-18NS pre-amplifier for review before anyone else. However obscure Switzerland's darTZeel may seem, it's now a global player in the extreme high end. And the pressure for the scoop review of their first pre-amp ramped up by a factor of 10 immediately after their NHB-108 power amplifier won a brace of awards from our friends across the Pond at Stereophile.

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According to the distributor, there was a queue of reviewers dying to get their hands on it, they had to fend them off with fears of the sorts of repercussions that follow bruised egos, why Kessler?, yadayadayada. So I suppose my offer to sleep with Serge and Her- no, that's a lie: I earned the privilege because I bothered to fly to Geneva, hang out with the pair, learn about the product and prove my worthiness. The latter might even be due to sharing a common taste in music with Hervé Delétraz.

Must've worked, because I've just spent a couple of weeks with the little beauty. No kidding: I do feel privileged. Yup, it's that good. And it' so fresh that it doesn't even have a blank name plaque in the upper right-hand corner; that awaits the engraving of the name of the eventual owner.

And having heard the power amp on numerous occasions, I can confirm that - unlike other situations where one part of a pre/power package preceded another, and Part 2 was a let-down - the darTZeel boys followed their debut with a perfect sequel. Think Godfather 2, The Two Towers or Attack of the Clones. Well, maybe not the Attack of the Clones. But you get the drift.

As with the power amplifier, darTZeel opted for direct paths and 'heightened minimalism' if such a phrase isn't borderline oxymoronic. As Hervé put it, 'Our dedicated circuits are reduced to their most basic form. As before, there is no application of any overall negative feedback. Because of this approach, the delicate, small audio signals amplified by the NHB-18NS only pass through seven silicon junctions, from input to output. And that includes the 13dB full discrete gain stage. And for the phono stage, we only add six junctions, for a maximum additional boost of 66dB, or 77dB in total.' Their minimalist circuits are currently 'patent pending.'

Despite the company's designers suffering an affection for the hideously coloured Rehdéko loudspeakers, they insist that the darTZeel goal is for untrammelled, pure and open sound. Amplifying the low level signals are discrete devices, or matched transistors embedded in dedicated integrated circuits. Hervé again: 'No operational amplifiers are used in the entire signal path. As in the NHB-108, all components used in the NHB-18NS preamplifier, with no exceptions whatsoever, are based on the finest products being produced by leading-edge industries at the present moment.'

This is where you start to get whiffs of the Swissness, which requires a brief aside about the 'Made in Switzerland' philosophy. First devised, adopted and safely guarded by the watch industry, that coveted identification of birthright is as closely protected as French wine's or cheese's 'apellation contrôlée', or olive oil's IOOC. darTZeel uses as many Swiss suppliers as possible, partly because the company jingoistically (but rightly) believes that the Swiss are the best at manufacturing anything made from metals, including electronic components, and partly so that darTZeel could become the only audio company to earn the coveted Swiss Label Certificat, attesting to its Helvetian purity.

Those of you who don't share, say, my obsession with Alpa cameras, watches and Nagra tape decks might wonder about the fuss, but - away from ultra-nationalistic Germans and Brits who refuse to believe that anyone could make things as well as they could - any form of proof that your wares are as Swiss as William Tell is akin to the Good Housekeeping Seal of Approval and an Appointment by the Queen all rolled into one.

So darTZeel has taken the best ingredients, and formulated a topology that includes the following strictures:

There are absolutely no contact or switches nor relay of any kind for source selection, all in the interests of absolute transparency. darTZeel prefers, instead of routing signals through a selector box, to provide each input with its own dedicated gain stage, enabled or disabled according to the user's choice. The signal is then directly routed to the volume control module.

In the NHB-18NS, the volume control module completely avoids the use of any potentiometer, stepped attenuator or analogue switch array in the signal path. According to Hervé, 'The sound signal is attenuated in a fully passive way, within a continuous range of close to 96dB in 192 steps of 0.5dB, in full analogue mode, without the use of any VCA or other active component.

'Both of these breakthroughs constitute a big step in the right direction: no harm to the signal. As mentioned above, this new design is patent pending. As soon as the patents are confirmed, darTZeel will be pleased to describe in detail how such signal treatment is possible.'

More Swissness: they adore secrecy. Just ask anyone who banks with them.

Further in keeping with the NHB-108 power amplifier, the NHB-18NS uses only small amounts of local negative feedback at the inputs, with one small, symmetrical loop of local negative feedback in the voltage gain stages. The output stages are open loop, and free of all negative feedback.

Within the 440x170x335mm (WHD) chassis is a modular frame, with every stage on a subassembly more like a computer or multi-channel A/V amp than a stereo preamp. Because of this, the unit might one day be customisable to a degree; at present, though, its modularity shows that the unit was designed from the outset to resist obsolescence.

Unusually, the company employs its own preferred, proprietary 50-ohm 'darT' outputs and 'Zeel' inputs with BNC connectors, alongside more conventional connections. As shipped and reviewed, the unit features a mix of six inputs covering phono, RCA/BNC and balanced XLR. As standard, these include a phono MM/MC input with gain from 30-66dB, a single 'full-floating' XLR input and four RCA/BNC 50 ohm Zeel inputs. Outputs consist of one XLR full floating output, three BNC 50 ohm darT outputs, ready for tri-amping, with optional built-in passive filters, a pair of RCA outputs and a pair of fixed RCA record outputs.

Read more about the darTZeel NHB-18NS on Page 2.

DarZeel-NHB-18-PreampReviewed.gifCompleting the package, and for many the most important part, is a feature shared by darTZeel's compatriots at Nagra: a battery power supply. Because the NHB-18NS is an 'authentic dual mono preamplifier, from input to output, with separate grounds for left and right channels,' each channel is battery-powered by its own battery bank, offering up to 15 hours of playing time on a full charge. Every input and output is treated to a 'very sophisticated, regulated and dedicated supply, ensuring the lowest power supply impedance possible.' And it's basically set-and-forget: automatic functioning allows full battery operation when listening, with the charging mode activated when the preamp is switched off. As Hervé puts it, 'Hum is gone forever, and there is no need to worry about knowing if batteries need to be charged or not.'

'Deliciously simple' described the front panel: source and volume rotaries marked 'Enjoyment Source' and 'Pleasure Control', an illuminated power on button called the 'Power Nose' (examples, I suppose, of Swiss humour), mono/stereo and mute toggles and a rotary balance which lowers one channel by up to 3.5dB while raising the other by up to 3.5dB. The back, on the other hand, is jam-packed. It contains all of the aforementioned input/output combinations and a multi-pin input to accept an umbilical from the outboard charger, along with earth tags for the phono section, toggles to apply 6dB of attenuation on certain inputs, and other toggles to defeat earthing in case of loops.

Other niceties include a beautifully-machined remote control for operating the volume; a home theatre bypass mode; multi-coloured LEDs to indicate battery status, charging modes, stereo mode, mono mode, mute, normal, etc.; and useful handles front and rear. The fit and finish are utterly and undeniably beyond criticism. Indeed, the only area one might possibly object to is the choice of gold front panel and red cover. It is, simply put, so frikkin' ugly that even a chav would find it objectionable.

But that's irrelevant. Within seconds of switching on, after allowing it to charge up fully, it was blatantly obvious that the darTZeel NHB-18NS goes straight to the head of the class. What we have here is one of those juggling acts performed only by the masters, that heady mix of delicacy and control, sheer musicality tempering almost clinical retrieval of detail, massive scale with no masking of the softest notes. And given its purely solid-state, Franco-Teutonic DNA, the shock is as great as hearing a German tell a joke. One that's actually funny.

I wish there were a way to provide a test CD that demonstrates when everything falls into place. It would include a recording that's 95 percent 'there', followed by the same again at 100 percent. Every pursuit has it, whether finding the perfect swing in golf, finding 'the line' on a race circuit, focussing a lens to perfection, burning in just the right amount of crunch on a crème brulée. The darTZeel does this over and over and over again. Even its phono stage, as set at the factory for median value m-c cartridges, obviates the need to look further.

Everything about the sound is carefully considered, of a whole, and in perfect proportion. From orchestral to unplugged soloist and every point in between - new, old, mono, stereo, digital, analogue - the darTZeel behaved with the kind of consistency that shrieks pedigree. It simply doesn't put a foot wrong, and even worst-case scenarios - CD transfers of 50s mono vocal discs - failed to reveal shortcomings. This pre-amp treats vocals, male or female, single or massed, with such utter respect that the sheer realism renders other systems artificial-sounding.

That stalwart, Keb' Mo', provided both melody and texture that tax most solid-state set-ups, which can never seem to get his rasp just so. They seem to amplify only the harsher elements of it, belying the warmth. Not so the darTZeel: it presented him front-and-centre, tall and noble, the voice a personal command performance, the guitar twanging for real.

Trying actively to upset the darTZeel revealed only one caveat: so clean is the sound that you may wish to play it louder than you might normally do, and I did manage to drive the matching power amp into clipping (as evinced by the LEDs). Even then, the clues were stern rather than shocking, and it never sounded like the system was about to implode. You'll be delighted to know that, wherever you dial the 'pleasure control', the scale remains consistent. You
'd have to go out of your way to get bad sounds from this. Like hooking up Rehdékos.

Then there's the entry fee. Even before you consider the NHB18NS pre-amp at 15,700, you really must consider its sibling, the NHB108B Power Amp, at an equally disturbing 11,490. Should such heady sums be within your reach, you will own a system to rank with the very finest that money can buy. And a mystery, too, will be solved. For those of you who have pondered for decades how the world's premier jazz festival ended up on the shores of a Swiss lake, wonder no more. Montreux: maintenant tout est clair.

Absolute Sounds
58 Durham Road
London SW20 0TW
Tel 0208 971 3909
Fax 0208 879 7962

100wd summary:
Make no mistake: the NHB-18NS pre-amplifier is exactly the mate for which the NHB-108 Model One power amp has been waiting. They complement each other perfectly, delivering a one-two punch that will knock a hole in the high-end solid-state sector. Admittedly, with a combined price befitting a decent car, you should be getting more than mere amplification, and you do: silky, seductive sound with power to spare. I suppose - were we to follow a car analogy - you could liken this in every way to a modern Bentley: sophisticated, capable of cosseting the owner, yet able to play the hooligan when the pedal is floored. Maybe labelling the volume rotary 'Pleasure Control' wasn't so daft after all.

We listened to:
Claudio Abbado/London Symphony Orchestra: Mendelssohn Overturen (Deutsche Grammophon 423 104-20) CD
Keb' Mo': Peace ... Back By Popular Demand (Okeh EK92687) CD
Mr. Big: Lean Into It (Atlantic 7567-82209-2) CD
Taj Mahal: Recycling The Blues & Other Related Stuff (Pure Pleasure PPAN31605) LP
The Who: Sell Out (Classic Records Track 613.002) LP

Review System:
Musical Fidelity kW25 CD player
SME 20/12 turntable, 312S arm, Transfiguration Orpheus cartridge
Audio Research PH5 and AudioValve Sunilda phono preamps
Wilson WATT Puppy System 7 and Tannoy Autograph Mini speakers
Yter and Acrolink interconnects
Yter speaker cables

Isol-8 mains regenerator


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