Solid State Power Amp Reviews

Delétraz also loves Peter Hammill and Van der Graaf Generator—"music from 30 or 40 years ago that's very ahead of its time. It's music that rejuvenates you from the inside; it cleanses you. To me, music is the essence of life in the universe. Everything is music. Sometimes you are glad, sometimes you are sad, but music is celestial. It's the expression of the universe as whole. I'm sure that the planets or the stars come together using some kind of music."

Delétraz ended by reflecting on his five decades in audio. "At this point, I have enough experience that if I design something, I pretty much know what it will sound like before I turn it on. I'm not 100% sure, but it's nice after time when you know how to tame the components and get a certain sound. It's like once you're a writer, you don't need to know how to write; you just write, and the words flow from your fingers. I'm able to design the way I do today because I started designing over 50 years ago when I was 8. So I'm lucky enough to be able to design these electronics, which we call 'instruments.' For me, they're like instruments. You play the music through them, and the goal is to bring happiness and a big smile to the listeners. That's my goal."

Moving forward
Delétraz was okay with using either his components' own footers or whichever equipment supports sounded best. For power, I took my cue from longtime darTZeel owner Fremer, who for years plugged his monoblocks into an AudioQuest Niagara 7000 power conditioner until, quite recently, he installed an Audio-Ultra AU Ultra Series 3000 portable power panel and made other major changes to his electrical system. I may have an eight-gauge dedicated line to my music room, but it picks up noise from two state-mandated breaker panels which in turn feed every noisy thing in the main house plus the heat pump, lights, and network front end in the music room.

Of the many things I want to do with that winning lotto ticket, upgrading my power is high on the list. I've not reviewed an amplifier that hasn't sounded best plugged into the AudioQuest. As was the case here.

On with the show
Of all the amps I've reviewed, the darTZeel NHB-108 model two's sound was the hardest to pin down. I was tempted to invoke the word "beautiful"—but saying that something sounds "beautiful" is, in the end, saying very little. So instead:

My very first listen was to the 2021 ECM release Uneasy from the Vijay Iyer Trio (24/96 MQA, Tidal), an anything-but-easy-listening jazz recording recommended by my neighbor Ray Schroff. Depth was beyond excellent: truly exciting. Cymbals were alive and believable, the midrange was smooth and inviting, and the piano's timbres were nigh perfect. Everything sounded superb short of Linda May Han Oh's bass, which was weaker than ideal and lacked ultimate pitch definition. No matter what music I played, the only thing lacking was stronger and tighter bass.

On Harmonia Mundi's Stravinsky: Histoire du soldat, Élégie, Duo (24/96 WAV), a fine recent recording of Stravinsky's delightful Histoire from violinist Isabelle Faust leading an ensemble of violin, double bass, clarinet, cornet, bassoon, trombone, and percussion, colors and contrasts were delicious and the presentation as fast and clear as I'd ever heard from my system. I jumped eagerly from violinist Patricia Kopatchinskaja and cellist Sol Gabetta's unbridled take on Leclair's wild Tambourin in C Major from Alpha's Sol & Pat (24/96 WAV) to Schnittke's Concerto for Piano and String Orchestra on a recent live recording from Yefim Bronfman and the Cleveland Orchestra under Franz Welser-Möst (26/96 WAV Cleveland Orch.), and beyond to King Creosote and Jon Hopkins's "John Taylor's Month Away" on Diamond Mine (16/44.1 FLAC, Qobuz) and Charlie Haden and Kenny Barron's "Waltz for Ruth" on Night and the City (16/44.1 FLAC, Qobuz).

Then I heeded a Facebook recommendation from Steve Guttenberg and explored a few tracks from Randy Weston's 1989 recording, Portraits of Duke Ellington (16/44.1 FLAC, Qobuz). Steve was recommending the vinyl, and I was listening to a CD-rez transfer, but that doesn't mean the recording didn't sound captivating; it did, save for some booming in the lowest reaches of the bass. Time and again, I noted how lovely and warm the midrange sounded, how realistically the piano resonated, and how airy and full the presentation felt. As I sat entranced by what to me sounded like African-influenced percussion on "Caravan, 1936," I got why Steve loves this album.

On a new Cedille recording Here With You: The Brahms Sonatas from Anthony McGill and Gloria Chien (24/96 FLAC, Qobuz), McGill's clarinet sounded so rich and colorful that it brought to mind the time I sat in the first row in UC Berkeley's Hertz Hall directly in front of Richard Stoltzman, during a recital in which his clarinet glowed with so much warmth that I wanted to take that sound home so it could fill me with joy for all my remaining days. Mezzo-soprano Alice Coote's wonderful, idiosyncratic recording of Mahler: Song Cycles (PTC5186576, DSD64 and 24/96 FLAC, Qobuz) with Marc Albrecht and the Netherlands Philharmonic Orchestra left my heart crying at the despair at the conclusion of Songs of a Wayfarer. Equally moving was the great Bettye LaVette's 2020 recording of Billie Holiday's "Strange Fruit," on Blackbirds (24/96 FLAC, Qobuz), which to these ears is more heart-wrenching than its creator's many versions.

Detail was remarkable. On Coote's Mahler, I discovered subtle inflections and vocal imperfections that had previously gone unheard. When I played Stravinsky's rhythmically jarring, profanely visceral The Rite of Spring on the superbly recorded live issue from the Seattle Symphony under Ludovic Morlot (24/96 FLAC, Qobuz), I heard numerous audience noises during the relatively quiet beginning of "Part 2: The Sacrifice." Ditto on the blessed mezzo Lorraine Hunt Lieberson's Live from Wigmore Hall recital of Songs by Mahler, Handel, and Peter Lieberson with pianist Roger Vignoles (16/44.1 FLAC, Tidal or Qobuz), where the teeniest cough, shuffle, or program rustle was audible. Welcome to the rare amp that manages to reveal the smallest details without sounding etched, hyperdetailed, or unnatural. Ever.

As for the bass: Listening to the lowest bass rumbles on "John Taylor's Month Away," Terje Isungset's "Fading Sun" from Winter Songs (16/44.1 FLAC, Tidal), and "Limit to Your Love" from James Blake's eponymous album (16/44.1 FLAC, Qobuz) clarified that the NHB-108 model two plumbs the depths. I would expect that through less-challenging loudspeakers with a more even impedance curve in the bass region, the darTZeel's bass will sound just fine. But through my Wilson Alexia 2s, the D'Agostino Progression M550 monoblocks' bass was incontrovertibly stronger, tauter, and, on growling electric guitar, nastier in a good way.

With darTZeel's NHB-18NS preamplifier
The NHB-18NS preamplifier proved the NHB-108 model two's ideal mate; it delivered new levels of believability, especially with darTZeel's Zeel 50 ohm BNC interconnects. On two of Delétraz's favorites, Roger Waters's Amused to Death (24/192 MQA, Tidal) and Pink Floyd's The Dark Side of the Moon (24/96 MQA, Tidal), the sound was as clear and mesmerizing as I've heard from my system. I couldn't believe how real Rickie Lee Jones's guitar sounded on "St. James Infirmary" from The Devil You Know (16/44.1 FLAC, Qobuz), nor how layered and natural the Portland State University Choir sang on the John Atkinson–engineered "The Heavens' Flock" from Eriks Ešenvalds: Translations (24/96 FLAC, Qobuz). Bass improved notably, especially on Waters's "What God Wants Pt. 1," and colors were the most saturated I heard through the NHB-108 model two. Even the slightest sense of a veil between me and the music vanished. Sensational sound became the norm.

Two very different "Red Book" recordings clarified what makes the darTZeel NHB-108 model two so exceptional. On Murray Perahia Plays Handel and Scarlatti (16/44.1 FLAC, Qobuz), the piano's overtones were more vibrant than I'd heard during the countless times I've played the recording at home or at audio shows. And on one of the great (albeit occasionally infuriating) recordings of Schubert lieder (songs), soprano Elisabeth Schwarzkopf's mono Schubert Song Recital with Edwin Fisher (24/96 MQA, Tidal), I heard subtle vocal inflections previously only hinted at. As easy as it may be to conflate "delicacy" with "lightweight," it was only through the darTZeel NHB-108 model two/NHB-18NS combination, joined by the Zeel interconnects, that I fully grokked that when designer Delétraz invokes the words "delicacy and grace," he implies strength.

Conclusion
DarTZeel's NHB-108 model two, the latest iteration of darTZeel's first product, is among the most satisfyingly musical amplifiers to ever sing in my system. Rather than hit you over the head with its strengths, it seduces with its exceptional embrace of music's essence. Details frequently submerged in the sonic fabric surface with a delicacy and rightness that illumine what you've previously been missing. This holds true for intimate solo vocals, classical chamber music, and big-boned rock, jazz, orchestral music, and opera. Especially when paired with its matching NHB-18NS preamplifier and top-line Zeel 50 ohm BNC interconnects, the NHB-108 model two sounds disarmingly transparent, real, present, and alive.

When matched with speakers that present challenging loads to amplifiers, the NHB-108 model two's bass can't equal that from more powerful amplifiers. Some who fall under its spell may be tempted to follow Delétraz's advice and change their speakers. There is an inherently nonmechanical, organic flow to the NHB-108 model two's golden sound that will keep enticing many a music lover back for more.