darTZeel NHB-18NS preamplifier

[Κώστας Φ.]

Description: Solid-state preamplifier.
Inputs: four unbalanced line-level (switchable between RCA and 50 ohm Zeel BNC), one unbalanced phono (RCA), one balanced (XLR).
Outputs: one unbalanced (RCA), one balanced (XLR), one buffered Tape Out (RCA), three 50 ohm darT (BNC).
Frequency responses (depend on measurement method): 1Hz–1MHz , +0/–6dB; 10Hz–100kHz, +0/–0.5dB; 20Hz–50kHz, ±0.5dB (XLR inputs & outputs).
THD: <1%, 7Hz–77kHz.
Signal/Noise Ratio: 100dB (A) line level; >70dB phono.
Risetime: <0.8µs.
Slew rate: >88V/µs peak–peak.
Crosstalk: below –90dB, 20Hz–20kHz.
Maximum output: not specified.
Input impedance: single-ended, not specified; balanced, not specified; darT, 50 ohms.
Output impedance: single-ended, not specified; 50 ohms darT output; balanced, not specified.
Weight: 57 lbs (26kg), including 6.5 lb (3kg) power supply.
Price: $23,250.


"The boutique company's second offering, the battery-powered NHB-18NS preamplifier, exudes darTZeelness, including a price of $23,250. Like the power amp's, the preamp's front and rear panels are finished in a dark gold that was a taste no visitor to my listening room managed to acquire. Not helping the Gold Acceptance Factor was the unusual retro-industrial red of the chassis, which was reminiscent of (take your pick): Radio City Music Hall before it was renovated, an 8mm projector from the 1940s, or an Erector set. Contrast the red and gold, add the two knobs' red LED backlighting and the three butterscotch indicator lights, and if it weren't a piece of electronics and didn't weigh 50 pounds, I could imagine finding one of these in Lauren Bacall's purse. But I ended up liking and understanding the NHB-18NS's warm, vivid color combination: The preamp looks like it sounds.

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Straight wire with gain?

Should a preamplifier be merely a traffic director, controlling the rate of signal flow and routing signals along chosen pathways while remaining neutral about what's passing through the pipeline? Or should it also impart a pleasing flavor to the proceedings?

These questions, long debated among audiophiles, are a waste of time, in my opinion. Anything inserted into the signal path will change the sound, even a passive volume control—especially if it's unbuffered. Those who seek some mythical "sonic purity" should probably give up audio and join a monastery.

Any audiophile who's bought a tubed preamplifier has decided to impart a particular sonic flavor to the proceedings. However, the same can be said of those who prefer solid-state preamplification. The conflicted choose hybrids of both technologies, such as my reference Musical Fidelity kWP. Whichever technology you choose, it should at least be quiet, dynamic, wideband, linear, and produce a low level of distortion. Both my listening and John Atkinson's measurements confirmed that the Musical Fidelity kWP, which isn't exactly inexpensive at $11,000, easily met those criteria (see Stereophile, December 2005), as did the three-box, $26,000 McIntosh C-1000, which I reviewed (and loved) for the August 2006 issue.

I haven't yet seen the NHB-18NS's measurements as I write this, but having listened for a few months, I don't doubt Delétraz's claim of quiet, dynamic, linear, wideband performance with low distortion (though the "less than 1% THD" spec isn't all that low). While 11dB isn't a great deal of gain, it proved more than sufficient when paired with any of the associated power amplifiers. No output impedance is specified for the unbalanced outputs, but based on my listening, especially comparing darTZeel's proprietary 50 ohm darT and Zeel connectors with standard single-ended types, it should measure sufficiently high to create no problems for most amplifiers.

Yet switching to the darTZeel NHB-18NS from the MF kWP produced profound sonic changes in my audio system, almost all of them much for the better, at least subjectively.

On first hearing, the darTZeel immediately revealed itself to be stunningly transparent, giving my Wilson Audio MAXX 2 speakers an electrostatic-like top end. Transient speed, resolution, and decay were nothing short of spectacular from day one, and that particular window on reality still retained its grip on my listening experience months later.

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Conclusion

Inserting the NHB-18NS into my already excellent-sounding system was like being in the middle of an otherwise grand tropical vacation and suddenly having all the bugs disappear. However, whether any part of the darTZeel's singular performance strikes you as oh-so-right or just too much will in part be determined by the associated gear, especially if your cables suffer from clogged sonic arteries, or your phono cartridge is ultra-lush. In fact, when I completed the darTZeel chain by listening to phono stage, preamplifier, and power amplifier, I found the combination a bit too lush, romantic, and—especially—dynamically challenged for my tastes. Switching to the Manley Steelhead brought the preamp and amp into better balance, but it has to be said that I'm used to high-current, high-wattage amplification.

No matter how good a piece of gear, it remains one ingredient in a recipe. That said, whether its minimalist circuitry provides purity by subtracting unwanted junk or by adding pleasing colorations, the darTZeel NHB-18NS is among a handful of the finest-sounding pieces of audio gear I have ever heard. Listening through it produced the same serenity I get every time at Avery Fisher Hall, just after the conductor's baton has gone down and the music has begun.

Reviewers can't seem to win. No sooner do I make an issue of actually having bought and owning the major building blocks of my reviewing system than I hear from a manufacturer and importer complaining that, when a reviewer buys his system, he's so "invested" in it that a competing component is less likely to get a fair review. In that manufacturer's opinion, long-term manufacturer loans to reviewers are actually preferable.

That I don't agree should be proven by my conclusion that the darTZeel NHB-18NS smokes the expensive preamp in which I've already invested. But just to keep that faction happy, if Hervé Delétraz wants to give me a long-term, semipermanent loan of the NHB-18NS, I'll take it." -- Michael Fremer


Και η ανταπόκριση απο τον πάγκο του John Atkinson:

"Though some aspects of its measured performance puzzled me, and I was not impressed with the behavior of its balanced inputs and outputs, overall, the NHB-18NS seemed well engineered." -- John Atkinson

Full Review: Stereophile.com