Pass Labs X1000 monoblock power amplifier Page 2

Interestingly, as far as bass is concerned, the X1000 wasn't the deepest-going or BIGGEST-sounding amp I've heard. Its sheer power was expressed more noticeably in the control, subtlety, and tonal shading at the bottom of the frequency range. It not only succeeded in driving along many a trip-hop and jazz session, but also fleshed out the acoustics and space of the recording venues. Transitioning up through the mid- and upper bass was smooth, seamless, and free of aberration, if a touch dry. That same lack of bloat, however, contributed to a high degree of detail and transparency. The lower midrange was similarly smooth, tight, and transparent, but as it rose into the midrange proper the real magic began. In a word, the mids were yummy, rife with detail, nuance, and texture, with a healthy dollop of velvet. Very, very attractive, even while remaining perfectly in control and tight as a drum.

The transition to the upper midrange and beyond was similarly unruffled and smooth. The highs, while nicely extended and linear, were in no way what I'd ever call sweet: The X1000 didn't sugar-coat. In fact, its utter control and grip extending into the treble made for some difficult listening on poorly recorded material. In that way, the X1000 was a bit of a snob—it was intolerant of bad recordings or problems anywhere else in the system. If anything was off, even by a hair, I heard it right away. It's just not an amp you can plunk down, plug in, and boogie down with. You've got to work at it, matching the front-end to perfection to achieve the X1000's considerable best. Without these efforts, you'll be left unsatisfied and frustrated.

The X1000s did very well in re-creating a recorded acoustic. Interestingly, this didn't take the form of heightened transparency or an enhanced sense of air. Rather, their perfectly adequate air might be characterized as a touch thick and humid. Though this sounds like a criticism, it's not—simply because the air the amplifiers did re-create was beautifully charged by the acoustics of the performers in the soundfield. The way the individual musical events propagated out toward me, and how they related to and interacted with each other, were superb.

Of course, this kind of power delivers shattering levels of dynamics, in both micro and macro senses. Yet I noted a lightness, a fleetness of initial transient and follow-on harmonic bloom that belied the X1000's huge existence and its powerful sound. This, I felt, helped quite a lot with the amps' superb imaging, even as I noted that they didn't focus quite so sharply on the image edge as some others do. Once again, given these beasts' overall balance and linear power delivery, that's not really a criticism either.

Roy Gaines' "Dreamgirl," on I Got the T-Bone Walker Blues (Groove Note GRV2002-2), is a real winner for music and sonics from Ying Tan. I pecked the following on my laptop while listening: "The upright acoustic bass is wonderfully extended and tight, very pleasing. It's defined not only by its own sound, but by the coupling of the instrument to the floor it's resting on, the type of floor that it is, the reverberant signature of the room—everything beautifully laid out and perfectly integrated by the amps." Check out the slight pop of Gaines' breath against the mike diaphragm 1:11 into track 4 on this album.

I suffered similar bass thrills while listening to Patricia Barber's Modern Cool (Premonition PREM-741-2), an album I'm crazy about that's also just come out on vinyl! Notes: "The quality of the bass sets the foundation preternaturally well, the refinement and pitch differentiation are remarkable. The sound remains palpable and very real-sounding, while at the same time stunning and communicative."

Given that, the X1000 also reproduced the piano with unusual grip and sweeping linearity. Listening to Alfred Brendel traverse my favorite Haydn piano sonata (in B minor, Hob.XVI:32), on 3 Piano Sonatas, Fantasia & Adagio (Philips 412 228-2), I noted the shimmer of the individual notes and the lack of bloat, every element individually explicated and in control, all bound tightly together and emerging whole, as music. This sonata depends for its success on nuances of timing brilliantly handled by Brendel, one of my favorite pianists—and, you might say, handled with equal aplomb by the X1000. Right on the pace with quick-step timing, the crystal-like bloom of each individual note was remarkable. The luminosity of tonal color was like a vintage champagne held up to the light. Man, I could almost taste it!

The detail coming through was also of a very natural quality. Consider "Rent Party," my favorite track from Count Basie Meets Oscar Peterson: The Timekeepers (JVC JVCXR-0206-2). Peterson is more closely miked than Basie; you can hear, with utter clarity, the sound of hammer against string and the follow-on acoustic. There's a superb delicacy of timing to the playing, which runs up a little before the beat at times, then a touch behind. It's obvious that these two guys are having as much fun with each other as is possible without getting arrested. And in that I found one of the most difficult expressions of musical playback to describe. It's that moment when the joy in the performance mingles with your own, a sort of commingling of music, emotion, and meaning. When an audio component allows that to come through unimpeded, well, that's a special component.

I had the same sense while listening to Ellington's "The Mooche" on Stereophile's new Rendezvous CD (STPH013-2). Instrument placement perfectly mirrored the layout captioned in the informative booklet. "Mooche" reached me as only a classic Ellington tune can. Jerome Harris and his quintet handle it with respect, love, élan, deep understanding, and unmistakable joy. You might feel, as I do, that the acoustic bass guitar is a touch light in the mix. But I found it very natural sounding, not overblown at all. Better a light touch reflecting the actual sound of the instrument—the stated goal of recording engineer John Atkinson—than the fat, bloated bottom end so many wild-eyed engineers conjure these days for the undiscerning.

I did find that inner light I'm so enamored of, that gives life to female vocals, especially. The X1000 had an essentially different sense of openness and light than I'd heard before—a presentation born of simplicity and purism, developing a light that seemed to ride between the activated molecules of sound. I had the impression the amplifiers were casting their light deep into the incredibly palpable nooks and crannies of the music. On good recordings, this allowed for Close Encounters of the Audiophile Kind, for which I suspect many of us continually search. On poorly recorded material, however, you might be better off with that inner light off. The Pass amps look on with only a stern, unblinking expression: "You are a shit recording. Begone." Purity has its price.

While some of my favorite chantoosies (Marianne Faithfull, Patti Smith, Patricia Barber) gave me goosebumps on my goosebumps, I actually enjoyed male vocals more with the X1000s. Listening to Bob Ludwig's transfer of Lou Reed's Songs for Drella, I felt Reed so real and present between the speakers that I could almost see the expression on his face. On my favorite track, "Faces and Names," I noted the lack of chestiness, which gave real lift and palpability to his voice.

Asymmetric conclusion
I'll always remember the X1000s: listening late at night with just the cool, eerie blue light of their meters shining like afterburners in some unimaginably powerful music machine. Their sound is related to the flat-from-DC-to-infrared Boulder 2050s, their build to the purist-bred YBA products: simple and elegant in conception and sound. Like the less powerful YBA Passions, the X1000s wed a sensitivity for small detail and nuance with Boundless Power, to produce a fine amalgam of the two.

Given that, other solid-state bruisers—the YBA Passions, the big Boulders, and especially the sexy and engaging Classé Omega—were easier to integrate with our system. The Pass amps required a bit more work; you'd better cultivate good relations with your dealer. But that would be recommended any time you're contemplating spending $24,000 for a pair of amplifiers!

While I agree with Nelson Pass that the X1000 is best served by a balanced differential input, the Nagra PL-P contributed a touch of welcome color I hadn't credited it with before. The Nagra's single-ended output nicely "balanced" the X1000 with the Canorus adapter cable. Straight out of the dCS 972 sample-rate converter and Elgar D/A, the Passes sounded a touch cooler with a few molecules of overcast, as it were. But that was neatly balanced by a satisfying purity of presentation and heightened imaging.

Supersymmetrical superamps. If you're a power user with a taste for the revealing, try them in your system. You might...Pass out and buy 'em.

Pass Labs
24449 Foresthill Road
Foresthill, CA 95631
(530) 367-3690