Tube Power Amp Reviews

The 1 2 3 speaker cable, so named because it's configurable for single, bi-, or tri-wired setup, is multistrand, uncoated, oxygen-free copper as well. The wire has a polyethylene dielectric, and it's wrapped around a hollow polyethylene tube, then PVC-jacketed. They're unshielded because, according to Joe, "the signal is pretty strong at that point, and we find that even in 45' runs some of our customers use in New York City, there's no RFI." The cables are $320 for an 8' pair, and bi- and tri-wired sets cost the same, with no additional cost for termination. A Signature speaker cable will soon be introduced.

Their attributes—excellent imaging, air, and dynamics (both micro- and macro-), great bottom-end heft and pitch definition, a clear and detailed midrange, and excellent highs (if not quite as extended as some of the multikilobuck cables)—worked perfectly in unison with the Manleys' own sonic characteristics. Believe me, I've played with the best, and these interconnects and speaker cables offer unbelievably high performance for relatively low cost. Sgt. Bilko-Scull: "Get out there and audition this stuff in your system right away! Ayyyy-up!"

I didn't mean that kind of feedback!
Centered on the face plate is a pair of old-fashioned knobs with which the user can change the feedback and associated slope through Minimum, Standard, and Maximum settings. Manual: "The feedback control varies the global feedback resistor in 2dB steps. This will change the gain and slew rate of the amp. The slope control varies the feedback slope capacitor value, which changes the amplifier's intended rolloff points at supersonic frequencies." You're advised to use your ears—which of course I agree with completely—and feel free to experiment.

Those still suffering from high Audiophile Rage Factor should avert their eyes, but for the rest of you, I found this set of controls very interesting indeed. They changed the sound in ways more subtle than choosing Triode or Tetrode operation. It all depended on the front-end driving the amps. For instance, the Forsell equipment is very open, bloomy, and spacious by nature, so I used Standard Feedback and Standard Slope most of the time. Maximum Feedback seemed to close the sound down slightly and fasten the bloom onto the image, as it were. With the vivid, incisive Jadis digital front-end, I usually found Minimum Feedback to work best with Standard Slope. Analog called for slightly different settings. Don't despair, it was basically a set-it-and-forget-it affair—I didn't find myself fiddling with it overmuch. start here

The magic output transformer
MAGIC: Multiple Arrayed Geometric Inductive Coupling transformer, featuring Basketweave Litz Interleave. Manual: "This is a truly new invention in output transformer design and manufacture, a very expensive piece as it requires that the bobbin (or coil) winding machines themselves be extensively modified because the winding procedure involves a complex shuttle and helical motion. The transformer achieves extremely precise coupling between all windings, especially between primaries and secondaries, which is how we achieve virtually zero insertion or efficiency loss and a phenomenal frequency response in the very low and super high frequency spectrum areas."

The Ever-Warm MAGIC transformers are stuffed into the Ever-Tight real estate available in the 440s in the right and left rear corners. The transformers are big, heavy lumps, and each amplifier has but a single small pair of custom-fabricated binding posts sticking out low on the rear panel. If your speaker cable isn't as flexible as the Discovery 1 2 3, you'll need to raise the amps on footers, or use a stand if you plan on bi- or tri-wiring them.

I experimented with a trio of Shun Mook Super Diamond Resonators and a quartet of Harmonix RF-66 Large Tuning Feet. I settled upon a trio of Michael Green AudioPoints under each amp: two at the rear under the transformers, the third centered up front.

Beauty & the beast
These amps were the very essence of the phrase "Made in the USA." They also suffered from multiple personality. Starting at the bottom, the bass sounded positively meaty (a word that popped up repeatedly in my notes). The LAMM M1.1s went deeper, but their bass was more lightweight and delicate than the 440s. I won't even mention the big Symphonic Line amps—their bass was from a different planet, okay?—The Planet of the Tight. The midrange of the 440s was plush and warm, the Discovery Signature delivering enough detail and texture to keep the illusion up. The highs too were sweet and inviting, if not as totally extended as the Jadis 200s (at twice the price).

But really, which amp sounded that way? For the 440s were possessed of two distinct musical personalities. Snapping the toggles up into Triode resulted in a tighter, but smaller and less impactful, bass; a midrange as voluptuous as Roger Rabbit's girlfriend; and highs as sweet as they come. The downside included a significant loss of both soundstage transparency and size, loss of dynamics (both micro- and macro-), and much less of that entertainingly vivid 3-D palpability factor.

Toggling down to Tetrode power mode for the full 440 was a whole different affair. On the Avalon Ascents (86dB sensitivity, 5.5 ohms minimum impedance), Tetrode sounded incredibly...powerful. The soundstage became huge, billowing, and so circumambient I felt like I was sitting in a Virtual Reality holograph of the acoustic. Tetrode bass was impressive as well: visceral, whacking, meaty, and totally kick-ass. (Art of Noise, Massive Attack, and Dead Can Dance, for example, sounded fantastic!) It was also somewhat more out-of-control, overripe, and voluptuous than in Triode. The midrange, too, lost some of its lushness, but it wasn't so sorely missed. The soundstage ambience and transparency, coupled with the sudden-impact 440W of Ever-Grip® tube power had on the Avalons, was astounding. The presentation was altogether faster, and thus more rhythmical and driving, in Tetrode.

But—and it's a significant "but"—it's the mid- to upper midrange and the highs where Tetrode takes the hit. The problem? Grain. Tetrode is more rough-hewn than Triode. Bright pop recordings with hashy top-ends could sound pretty bad. If this grain offends, drop 'em into Standby, wait a sec, snap the toggle to Triode, and bring the power up again. Certainly, a few really lousy recordings still sounded like hell in Triode. The 440s did change their tune depending on the recording, and even the front-end employed. The Jadis and Forsell DACs were truly well-differentiated from one another, for example.

In spite of reflecting what's upstream, they're still not reviewer's tools. And to be fair, no one implied they were. Instead, I see a hippy-dippy pony-tailed MTV-approved producer waving his arms around, exclaiming, "What?! You never heard tubes before, man? Listen to these!" And everyone would be impressed. I mean, what's the problem? Big impressive bass, a rich and attractive midrange, illuminated and perfectly sweet highs, and imaging abilities up the wazoo. Where, exactly, is the beef?