darTZeel NHB-458 monoblock amplifier Page 3
The NHB-458s nailed that record, as it did Wilkie's recording of Vladimir Ashkenazy and Georg Solti performing the Beethoven piano concertos with the Chicago Symphony (LP, Decca SXLG 6594-7)another set that would sound good on a boom box. Through the NHB-458s, the piano's textural and tonal clarity and physical focus were a few significant steps better than what I've heard from the other amps mentioned.
Could the darTZeels rock? With that much power, you'd think their dynamic possibilities would be unlimited. You'd be correct. What's more, the more I cranked them, the better they sounded. They never got hard or brittle, but seemed to always sound . . . just right. XTC's superbly recorded and mixed masterpiece, English Settlement (2 LPs, UK Virgin), has sounded spectacular ever since the first time I played it, through Spica TC-50s, in 1982. Through the NHB-458s, it sounded so good, and so much better than I'd ever heard it, that I laughed out loud. Track 1, "Runaways," is a densely packed, chant-like track with an impenetrable overlay of jangly guitars anchored by thundering bass drum and thick, undulating bass guitar. The NHB-458s reproduced the bass line with an ideal mix of control and textural elasticity, to give it the desired "sticky" feel, in front of which the curtain of jangly guitars sat well forward, spatially farther separated from the bass parts than I can ever recall hearing, and so fast and precisely rendered! If you love this album, as I do, I wish I could sit you down and play for you "Yacht Dance": so delicately drawn, yet so three-dimensional and so physically solid. The handclaps had never sounded so well fleshed out. In fact, handclaps in general, whether on the Beatles' Abbey Road or Mel Tormé's audience at Marty's, had never sounded quite so fleshy or real.
The new vinyl reissue of Paul Simon's masterpiece, Graceland (LP, Columbia/Legacy), was cut to lacquer (as opposed to DMM for the 1986 release) from the original analog tape by Ryan Smith at Sterling Sound, who learned the trade from veteran George Marino. This LP demonstrated everything great about the NHB-458: "rapid response" speed, dynamics, transparency, tonal and textural finesse, and, especially, soundstaging. The amp's ability to cleanly and transparently layer instruments in three-dimensional space was superior to anything else I've heard.
In "Diamonds on the Soles of Her Shoes," Ladysmith Black Mambazo's opening chant, split between the channels, attained a hair-raising level of transparency and three-dimensionality, while the drum thwack that introduces the melody exploded from the left channel with alarming power and textural suppleness. As the "ta-na-nas" faded out at the end, everyone who sat and listened, from manufacturers to friends to John Atkinson, and without exception, exclaimed, "Wow!"
Caution and Zeel Listening
After a few weeks of happyno, ecstaticlistening, the Wilson MAXX 3s were wheeled out to make way for the Joseph Audio Pulsars, which I reviewed in June. The NHB-458's manual includes enough cautions about connecting and disconnecting speakers and preamps to give me pause about the amp's robustness and stability in the event of, say, a shorted speaker cable. Before disconnecting and connecting cables, you're warned to shut off the amp, disconnect the power cord, and wait a few minutes. Because of the NHB-458's power reserves, lethal voltages can be present at the speaker terminals. which partly explains the cautions.
So I was cautious. Anyway, the Cardas speaker terminals make it just about impossible to cross spades at either end. Using a flashlight, I double-checked all connections before plugging the darTZeels in again.
I turned on the left amp without incident. When I powered up the right amp, it went through its normal startup routine, but as soon as the relay clicked, there ensued a catastrophic, almost violent meltdown that I could see and smell. For this part of my listening each NHB-458 was plugged into a Shunyata Research Triton power conditioner. Its circuit breaker blew; unfortunately, the one on the right NHB-458 didn't. I have no idea what caused the amp to malfunction, but it had to go back to Switzerland for repairs. With a friend's help, I carefully repacked it in its shipping crate, but had forgotten to secure the suspended subchassis with the four bolts, which caused additional damage by the time the amp arrived back in Genevafor which I profusely apologized to Hervé Delétraz.
The only good to come out of all this was that nothing I substituted for the NHB-458s came close to approaching their spectacular sound. When the repaired amp was shipped back and the NHB-458s once again powered my system, sonic bliss returnednot that the other amps had caused any suffering in the meantime.
At Delétraz's urging, and because I own one of his NHB-18NS preamps, I had substituted his 50 ohm, BNC-terminated, coaxial Zeel interconnect for my TARA Labs Zero. I don't have the space here to discuss transmission-line theory, or why Delétraz believes his Zeel connection is superior to any standard interconnect, especially in terms of eliminating electrical reflections. (Years ago, before he began making amps and preamps, he wrote a paper about this for Stereophile's November 2001 issuealso see this article.) In any case, the relatively inexpensive Zeel cable connection took everything I've described above to an even higher level of clarity, dimensionality, and harmonic and textural purity.
If you've already concluded that the darTZeel NHB-458 is easily the finest power amplifier I have ever heard in my listening room, you're correct. It combines lightning-stroke overall speed, effervescent and precise high-frequency transients, and unlimited dynamic capabilities at both the macro and micro levels, with supple and delicate yet powerful bass, and transparency that surpasses anything else I've heard at home. And it does all of that without sacrificing any of the harmonic riches and/or textural performance that speedy amps usually jettison. There was nothing cool, clinical, or analytical about the utterly transparent sound produced by the NHB-458s. Nor, after months of listening, could I detect any obvious colorations or artifacts.
While I don't know what caused the meltdown of the right-channel NHB-458, I've been told by one admittedly biased overseas darTZeel distributor that he's sold more than a few pairs, and none of his customers has experienced any problems, let alone such a catastrophe. So don't let my bad experience influence your decision. If you're fortunate enough to be able to afford a pair of these amps and you're not a single-ended-triode guy driving big horns with a few watts, you should hear a pair of NHB-458s in your system.