Solid State Power Amp Reviews

Every time a new audio technology enters the marketplace, a debate begins about its relative merit. That debate never ceases, even decades after the technology first came (and sometimes went). Turntable platters driven by belts vs rims vs idlers vs directly by their motors. Analog vs digital. Tubes vs solid-state. Triodes vs pentodes, Single-ended vs push-pull. Objectivism vs subjectivism. The power and seriousness of each of these debates has splintered our global hobby into diverse tribes, cults, and subcults—and therein lies one of the chief joys of being an audiophile: participating in cult rivalries.

I belong to all of these cults, and simultaneously subscribe to most of their conflicting theories—especially the ones that lean toward the principles of "less is more" and "keep it simple."

I've also started my own cult—I prefer to call it a school—founded on the ancient tradition of Taoist master and humble pupil. My cult strongly believes that the dominant principle behind all genuine invention is the chi of the designer. So instead of joining, say, the idler, triode, and hornspeaker cults, I prefer to study the paths of such living chi masters as Mike Moffat, Charles Hansen, John Curl, Frank Schroeder, Gordon Rankin, Mark Döhmann, Andrew Jones, and—last but far, far from least—Nelson Pass, who tends to speak with the wisdom of a chi master: "There are two most essential principles to audio design. The first is simplicity. The second is linearity."

A Zen of Few Watts
Okay, all you high-rolling audiophile know-it-alls—what is the argument against amplifiers that operate in high-bias, class-A, single-ended mode, with the lowest possible parts count? Is there a better strategy for beauty, rhythm, color, texture, and easy-flowing musical verity? I think not. And please explain: Why has mainstream audio gone to such ridiculous and expensive lengths to avoid building and selling precisely these sorts of amps?

In response to such questions, Nelson Pass—of Threshold Audio, Adcom 555, and Pass Labs fame—established a kitchen-table skunkworks, First Watt, to explore alternative amplification "With oddball characteristics and output power ratings of 25 watts or less." Since its founding, in 1999, First Watt has developed over a dozen unusual, low-powered, but famously musical amplifiers, as well as five unique "line stage products" that include buffered passive volume controls and active crossovers.

Description
I am currently enjoying First Watt's J2 stereo power amplifier ($4000). Outputting 25Wpc into 8 ohms or 13Wpc into 4 ohms (footnote 1), it's a single-ended, class-A, direct-coupled, current-source design with just two stages, both JFET: one for voltage gain, the other for current delivery. A light touch of feedback is used to reduce the output impedance to just 0.4 ohm. Happily, the input impedance is 100k ohms, so the J2 can be used with most any preamp, tubed or solid-state. The J2's voltage gain is 20dB, its damping factor into 8 ohms is 20, and it has both balanced (XLR) and single-ended (RCA) inputs. On the front, two blue-green "on" lights peer through a simple old-school faceplate. Nelson Pass: "Looking for tomorrow's faceplate with yesterday's circuits? You're in the wrong place."

The Tao of Listening
I used several excellent preamplifiers for this review, but most of the critical and musical thoughts I here commit to print were formed with Pass Labs' HPA-1 line stage/headphone amplifier driving the First Watt J2. To assess how the J2 handled a variety of loads, friendly and not so friendly, I organized my listening around the bevy of speakers I had on hand at the time.

With Zu Audio's Soul Supremes
While writing my review of Zu Audio's Soul Supreme speakers, I knew that Zu's owner and designer, Sean Casey, recommends amplification by Nelson Pass. So I borrowed a friend's First Watt J2 to hear how it would do with the Souls, whose sensitivity is 96dB and nominal impedance 16 ohms. Instantly, my whole system lit up and danced. Bounce, drive, pace, rhythm, and melody grabbed hold of my consciousness. I was gobsmacked. Rarely have I experienced an amplifier that did not over- or undercontrol the speakers it was partnered with, and thus dash all hopes of frolic and bounce. But in that regard, the J2 felt uncommonly perfect with the Zus. The First Watt was Fred Astaire, the Soul Supremes were Ginger Rogers, and . . . the results were much more than entertaining.

I wondered: Where did all this beguiling vivo suddenly come from? Record after record, I kept musing: What was up with these hypnotizing momentums? How did this wide-open midrange and triode-like top end happen?

And, more important, where did all this old-school authenticity and organic black soul come from? I'm listening to the title track of Nina Simone's 1958 debut album, Little Girl Blue (LP, Bethlehem BCP-6028), and feeling solidly connected to the singer, her time, her attitude, and her beyond-amazing piano work. Her fingerings were so decisively rendered that I remembered when a reporter asked her why she had to spoil her career with all that civil-rights activism, and she replied, "Because you wouldn't let me play a piano at Carnegie Hall." Brava Nina! Bravo J2!

At my house, the J2 played the Soul Supremes ($4500/pair) with more melody-tracking connectedness than any other amp I've tried with the Zus. Think grainless images and head-shaking rhythms. Every aspect of the music—pace, presence, performance—was fully exposed. Bass was just-right tight, not too fat or lean. I was so bouncing-up-and-down impressed that I wrote to Nelson Pass, imploring him to send me a review sample of the J2.

With DeVore Fidelity's Orangutan O/93s
I used to spend countless late-night hours in the classical section of Tower Records, looking for spellbinding, emotionally powerful, spiritually elevating performances of music by J.S. Bach that might also have been divinely recorded. Unquestionably, my greatest spiritual-audio find was the 1961 recording, by Otto Klemperer leading the Philharmonia Orchestra and Chorus and the Hampstead Parish Church Boys' Choir, of Bach's most sublime creation: the St. Matthew Passion (3 CDs, EMI CD 5 67542 2). It features Peter Pears, Dietrich Fischer-Dieskau, Christa Ludwig, Elisabeth Schwarzkopf, Walter Berry, and Nicolai Gedda. Most important, Klemperer's extremely slow, dark, unabashedly romantic reading stimulates something very strong inside me—and the sound quality plays no small part in facilitating this effect. Driven by the First Watt J2's 25Wpc, DeVore's 10-ohm Orangutan O/93s took me deeper than ever before into Bach's fusion of the liturgical and the dramatic.

My hat is permanently off to producer Walter Legge and balance engineer Douglas Larter—and to Andrew Walter, who remastered this recording for CD: chi masters all. Listening to this was high-level church—so please don't ask me to talk about highs, lows, or midranges. I refuse to listen for bass quality while wiping away tears of awe and love for nearly four hours! (Klemperer's is longer than any other recording of this Passion.) All I can say is that there was never a bad note of any kind—I played this music extremely loudly, and heard no hint of distortion, brittleness, or stridency. It was a perfect-storm demonstration of why I am an audiophile and a student of music. We all venerate different earthly and heavenly forces, but I believe that this sublime combination of composer, music, amplifier, and loudspeakers might be difficult to better at any time or any price.

With Dynaudio's Excite X14s
The Dynaudio Excite X14s are a little lower in sensitivity (85dB/2.83V/m) and impedance (8 ohms) than either of the speakers discussed so far. With the J2, they sounded rich and well-toned, but also dull and lifeless. The modest Dynaudios needed more push and power than the First Watt could provide.

With Falcon Acoustics' LS3/5a's
With an impedance of 15 ohms and a sensitivity of 82dB/2.83V/m, Falcon's LS3/5a speakers image like an old Leica: solidly 3D. Foreground, middle ground, and background were unmistakably differentiated; recordings sounded wide, deep, fully open. The First Watt J2 enhanced each of these admirable traits.

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Footnote 1: These are the specs published on the manufacturer's website; according to the J2 owner's manual, the output power is 30Wpc into 8 ohms and 13Wpc into 4 ohms.