EAR 912 preamplifier

My opinions keep changing—more evidence of life before death, I suppose—including my thoughts on audio-system hierarchies. I used to think that preamps were among the most sonically influential components, certainly more so than power amplifiers. I'm not so sure anymore (footnote 1).

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That doesn't leave much to write about whenever a new preamplifier does come my way, so I'm filling the void with my expanding concern for creature comforts: More than anything else, the preamplifier is the ergonomic focus of any decent music system, so I'm here to praise it for that. Now I've got something to care about again.

Viewed in that light, Esoteric Audio Research's brand-new EAR 912 control preamp (EAR's UK website calls it a Professional Tube Control Centre) seems to have been lifted from my dreams. A true full-function tube preamplifier—it combines line-level gain with phono gain and equalization—it's equipped with two pairs of equally configurable phono inputs, internal moving-coil step-up transformers, a mono switch, six pairs of line-level inputs (two of them balanced), two pairs of outputs (one balanced), and, best of all, a pair of VU meters. If you're wondering why I've never mentioned a need for VU meters, it's because I wasn't aware of it until now.

I'll get back to those in a minute. But first, let's have a look at the EAR 912's basic architecture.

Design
EAR's Tim de Paravicini has designed his newest preamp around the 7DJ8 dual-triode tube (called the PCC88 in Europe). The EAR 912 uses three of them in the phono stage—where one tube splits its chores between the two channels—and another two for the line stage. As the renowned Mr. de P told me recently, the 7DJ8 is a tube he knows well, having designed a fair amount of his pro gear around it, and he points in particular to its exceptionally long life. (The arguably more common 6DJ8 can be substituted, if desired, notwithstanding a slightly different filament voltage requirement—although in such a case it's best to replace all the tubes in a given stage at once.)

The '912 isn't the first EAR preamp to use internal step-up transformers for moving-coil cartridge gain, but it is the first in which those trannies are addressed by two different pairs of phono inputs. There's a selector knob on the front panel for choosing which input pair is active, as well as another for selecting the desired transformer primary—3, 6, 12, and 40 ohms are the nominal impedances, corresponding with respective additional gains of 30, 26, 23, and 20dB—or for bypassing the step-up transformer altogether, as with a moving-magnet cartridge. The EAR 912's phono section remains iron-rich even so: Its RIAA equalization circuit uses a pair of custom-wound inductors, which de Paravicini selected for being less prone to overloading and ringing than capacitors, and the transition from phono stage to line stage is accomplished with a pair of similarly bespoke coupling transformers.

The transformer approach was chosen not only for electrical efficiency and purity of sound, but for flexibility in use: A three-position attenuation knob on the front panel allows the user to choose between multiple secondary windings on the interstage coupling transformers—for full gain, –6dB, or –12dB. That control, used in tandem with the one for selecting the appropriate step-up transformer primary windings and the step-up transformer bypass knob, provided the highest level of flexibility I've ever enjoyed in a phono preamp. As I write this, I have a Rega turntable with a Linn Adikt MM cartridge connected to the EAR 912's Phono 1 input, and a Linn LP12 turntable with a Lyra Helikon Mono MC cartridge connected to Phono 2—and this is only one of many combinations I've happily used over the last couple of months.

That's also where the meters come in, literally and figuratively: Right before the line stage's volume control, two custom-made VU meters measure voltage on an average rather than peak basis—the idea being to approximate the loudness of the music overall and not to telegraph to the user every last transient spike. Here again, de Paravicini's years of experience designing studio gear paid off: "The Bell Labs specs from the 1930s called for a 'spade' pointer, and even required a certain yellowness of the background," he told me. "That way, you were able to see what the meters were indicating from across the room: You didn't need to know precisely what number the needle was pointing at any time." The EAR 912's meters follow suit, and during my time with the EAR 912 they proved enormously useful: By working with the controls described above, I was able to use the meters to help find the settings that were right for every different phono cartridge, representing a wide range of internal impedances and output voltages.

The meters also respond to line-level signals, of course, which can travel their way from a brace of single-ended and true balanced inputs, the latter having their own input transformers. Sadly, and through no fault of de Paravicini's, watching the meters during CD playback wasn't half so joyous as during phono use: They don't shrink from telling the user how badly mastered (as in: wildly, excessively hot) most contemporary recordings appear to be. Which is depressing.

A final design touch worth noting: In addition to the ones already mentioned, and the one you'd expect to be at the heart of its power supply, the EAR 912 contains two more custom-wound transformers: These are output transformers, used to keep the preamp's source impedance low (and, of course, to block DC, should it amble past by mistake). Each of these has two secondaries: one for feeding the single-ended (RCA jack) outputs, which are grounded, and the other for feeding the balanced (XLR jack) outputs, wherein the ground is floated. Both sets of outputs can be used simultaneously, as with a subwoofer or some other device that accepts a line output.

The EAR 912 is a visually striking piece of gear. I love the looks of the thing, and the proportions. It's tall because it needs to be: The backs of the meters need to clear the circuit-board components below, among other things. But it doesn't need to be especially deep, so it isn't. The metalwork is exceptionally sturdy and well finished, with thick semigloss enamel throughout and a black anodized front panel with no unpleasant edges. For once, rack-style handles on the front are more a necessity than a mere boy-racer affectation (like spoilers): With all that iron inside, the EAR 912 isn't as easy to lift as most other preamps.

But lift its 29 lbs I did, substituting the all-in-one EAR 912 for my reference combination of Fi preamplifier and Tamura TKS-83 moving-coil step-up transformers. The Fi is rare enough these days, inasmuch as it combines line-level gain with phono equalization and sufficient additional gain for MM pickups, and although it doesn't have transformers for interstage or line-output coupling, the Fi does use the comparable 6DJ8 tube throughout: an interesting comparison.

Sound
I did most of my early listening with a Linn LP12 turntable with Ekos tonearm and my Miyabi 47 phono cartridge: low output, and very low internal resistance. I determined that using the EAR 912's 3 ohm step-up transformer primary with full (–12dB) attenuation was best for the Miyabi—and it was then that I heard at least one aspect of the EAR 912's superiority to my reference gear: The EAR was unusually noiseless, with very little tube "rush" and literally no hum, even with the ground leads from the Linn Ekos and Rega RB300 tonearms left unconnected.

Maybe that's what made the EAR so good at retrieving very subtle details, such as the distinctive attack, sustain, and decay of the big orchestral drum in mezzo-soprano Janet Baker and conductor Sir John Barbirolli's famous recording of Elgar's song cycle Sea Pictures (LP, EMI ASD 655). Similarly, I noticed trills on the flute I'd never noticed before in the first movement of Brahms' Symphony 2, with Leonard Bernstein and the New York Philharmonic (LP, Columbia D3M 32097). And tape splices and microphone punch-ins on my favorite pop recordings—listen to how the "room sound" changes just before Paul starts singing on the Beatles' "Let It Be"—were laid completely bare.

For the most part, the musical and sonic performance of the EAR 912 didn't depart significantly from that of other top-class preamplifiers I've had in my home—including the Lamm LL2 Deluxe (reviewed in the September 2005 issue) and the Audio Note M2 Phono (June 2004), as well as my own Fi. All four are substantially, timbrally uncolored things, though the Audio Note is probably the "darkest" of the bunch, and all of them get the basic pitch and timing information right. All four are also capable of being emotionally thrilling, though I'd give the Lamm a slight edge for stripping the greatest amount of crud away from the notes and thus seeming to let the music breathe to the utmost. (But I admit that that comparison is flawed: The Lamm is a line-level preamp, and I've heard it paired only with phono sections from other makers.)

But I dare say the EAR 912 is the most dramatic sounding of the lot. I never once heard it compress the signal, regardless of the record played. And it allowed music to come through with so much of its intensity and nuance intact that literally everything I played was impossible to ignore. One afternoon in particular, when I was hooking up my mono record player to use as a source with one of the EAR 912's phono input pairs, I chose the great UK release of André Gertler performing the Berg Violin Concerto with Paul Kletzki and the then-new Philharmonia Orchestra (10" LP, Columbia 33C 1030). I was actually a bit peeved at first, because I had to stop what I was doing and sit down. Of course, my annoyance quickly turned to rapture as the system brought me another step closer to understanding what Berg had had in mind.

But the truth about the EAR 912 could be had by letting it play simpler music—and by hearing how it helped to pull levels of meaning, of emotional and intellectual engagement, out of what would otherwise be just electromechanical noise. Dylan's "The Lonesome Death of Hattie Carroll," from The Times They Are A-Changin' (mono LP, Columbia/Sundazed 5108), was appropriately moving—besides which it simply sounded fine, with superb vocal presence and a well-textured acoustic guitar sound. And pianist Witold Malcuzynski's sophisticated but almost offhand approach to Chopin's Waltzes (LP, Angel S 35726; CD, EMI Classics 5 68226 2) was complemented by the EAR 912's good sense of flow and momentum: Its sound on these recordings was as nonmechanical as it gets.

A note on spatial performance: Like the other preamps I've mentioned here, the EAR 912 tended toward a big sound: a wide, deep soundfield that always seemed capable of sounding even bigger when the need arose, with stereo imaging that sounded more real to me than the overly precise sound I associate with the high-end audio salon experience. The only departure from that was when I used an MM cartridge with the EAR, bypassing the step-up transformers altogether. When I did that, the soundfield was noticeably more distant, albeit not unpleasantly so. I have no idea what could account for that, but when I tried driving the EAR 912's phono stage with other, non-EAR trannies, mostly in an effort to see how the integral ones fared against the competition, the sound had consistently greater scale with the iron in line than without.

And how did Tim de P's trannies stack up? Quite well, I think. In direct comparisons I preferred them to my Audio Note AN-S2 (though some readers might consider the test to be flawed by the fact that the outboard unit required an extra interconnect in the chain), and while I thought the Tamura sounded still clearer and more natural (so much for the cable excuse), the difference was modest.

Summing Up
Modest differences are, as I've suggested, no strangers to the modern-preamp landscape—but the functionality and flexibility of the Esoteric Audio Research EAR 912 are anything but common. This product taught me something about my records and the other components in my system, and I enjoyed every minute I spent with it. The EAR 912 isn't cheap, but it's a Class A preamplifier in every sense, and an heirloom-quality instrument that represents the apex of both build quality and design ingenuity. I miss it already—and I strongly recommend that you try to experience it for yourself.



Footnote 1: Why is it that most of us can name at least a dozen vintage power amps we wouldn't mind owning—Quad II, Western Electric 93, Dynaco Stereo 70, Marantz 9, et al—but probably fewer than two or three vintage preamps?
COMPANY INFO
Esoteric Audio Research/Yoshino Ltd.
US distributor: EAR USA, Inc.
1087 East Ridgewood Street
Long Beach, CA 90807
(562) 422-4747
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