Tubes or transistors: on which side of the great amplification debate do you fall? Often the answer has to do with your choice of speaker, but not always -- you may have chosen your speakers to complement an amp you love. So it goes -- until now. There's a new game in town -- digital amplification. Yes, Spectron and TacT have produced digital amps for some time, but I predict that an amp like the Bel Canto EVo 200.2, which has morphed into 200.4 and 200.6 multichannel versions, will finally have us understand the promise of digital amplification.

Bel Canto Design of Minneapolis, Minnesota has made fine tube-based products for years -- and still does. I reviewed the company's SETi40 integrated amp two years ago, and it's a really fine-sounding piece of gear. But a change in direction began to rear its head with Bel Canto's introduction of the DAC1 digital-to-analog converter, which eschewed the use of tubes but did include upsampling and internal jitter reduction. The DAC1 was an overall forward-thinking design that won our Design Innovation award for 1999.

Shortly after our review of the DAC1, Bel Canto began hinting about a new amplifier they were very proud of, and then showed the amp, the EVo 200.2, at CES 2000. We arranged then for a review, which has taken a while to appear due to various scheduling concerns. We may not be the first to review the EVo 200.2, but….

Inside the box

The $2395 USD EVo 200.2 is an unassuming-looking amplifier -- a smallish black box (17"W x 16"D x 3 1/2"H) with only the Bel Canto logo and a power-indicator LED on the front. It's also light, 35 pounds in its shipping carton. By high-end-audio standards, the EVo 200.2 looks more like a phono stage than an amplifier; there aren't even any heatsinks visible!

But no heatsinks need to be visible -- or be used at all -- because of the amp's Tripath class-T, "high-efficiency digital power processing output stage," which uses two N-channel MOSFET switches between the power-supply rails, hence the more commonly used name for digital amplifiers: switching amps. These switches turn on and off at a rate of over 600,000 cycles per second and are isolated from the loudspeaker by a single inductor/capacitor filter that removes energy above 80kHz. But the story doesn't end here. The digital power processor used in the EVo 200.2 adds small levels of dither to the signal to ensure linearity from very low to very high output levels. The digital power processor also controls "the critical timing information" of the amplifier, changing the switching frequency, spreading the digital energy over a wide bandwidth, and reducing the energy at any one frequency.

The point of all this is that the EVo 200.2's circuitry does some interesting things, some of which tube and solid-state amps are not capable. Consequently, the EVo 200.2 doesn't look like a power amp that delivers 120Wpc, and it doesn't draw the AC of such an amplifier either. Bel Canto recommends leaving it powered at all times, and I can only concur. And because it draws so little power, it runs very cool, only the smallest bit warm to the touch. All that processing power ensures that the amplifier outputs the energy it takes in as power, not heat.

On the back of the EVo 200.2 are the main on/off switch, pairs of good-quality speaker binding posts for the left and right channels, pairs of RCA and XLR input jacks, an IEC receptacle for the power cord, and a push-button switch for easy bridging of the amplifier to mono, in which case it delivers a whopping 400 watts. The advantages of mono use may be greater than the extra power, as the EVo 200.2's power supply will effectively be powering only one channel, which should, according to Bel Canto's John Stronczer, lower distortion. Even with the EVo 200.2 in stereo mode, Bel Canto claims 30 amps of peak current delivery, so the amp should be able to handle a good number of current-hungry speakers.

System

I used the EVo 200.2 exclusively in my reference system, where it powered Wilson WATT/Puppy 6 loudspeakers. Preamps used with the amp were from Lamm, the L1 and L2, and other amps on hand were the mighty Lamm ML2 monoblocks, Audio Research ATM200 monoblocks, and the Mark Levinson No.383 integrated amp. Digital sound came via a Bel Canto DAC1 (recently upgraded to 1.1 status) or Perpetual Technologies P-1A/P-3A combo driven by either a Pioneer DV-525 DVD player or a Mark Levinson No.39 CD player. I also used the No.39 without the Bel Canto or Perpetual DACs and straight into the EVo 200.2. Interconnects and speaker cables were from JPS Labs (Superconductor2, NC Series), Nordost (Quattro-Fil and SPM Reference), TARA Labs (Air One), and DH Labs (Air Matrix and Q-10); an equally diverse collection of power cords was used, including models from Shunyata Research (Sidewinder, Sidewinder "Venom," Black Mamba, Viper and King Cobra Version 2), ESP (The Essence), JPS Labs (Power AC and Kaptovator), TARA Labs (RSC Decade and RSC Master), and Audio Magic (Xstream Silver Power). All components sit on either a pair of sand-filled Target equipment racks or Bright Star Big Rock bases.

In terms of power delivery, I used the EVo 200.2 straight into the wall, with a Shunyata Research Hydra power-line conditioner, or the PS Audio Power Plant P300. The amp registered as using only 30 watts from the P300, which also makes it one of very few amplifiers you can use in this way.

Perfect sound forever?

In his review of the Wavac MD-300B amplifier, Bill Cowen came up with an ideal definition of what SET amps do so well: "reproduce the fine harmonic detail, structure, and natural development (and decay) of every note." What this implies is that SET amps seemingly break down the music into individual events and handle each of these as separate entities. There is something noticeably special, at least to my ears (and obviously Bill Cowen's too) about SET sound -- and it's not easily defined by the standard lexicon of audio verbiage.

The same holds true for the EVo 200.2. There is an obvious and ample ease to the sound it produces, and this is not due to any tonal tom foolery, but more in the way the amplifier addresses every note -- each sonic event. Spain's Blue Moods of Spain [Restless 72910] was illustrative of this, as the music on this disc simply loped along, as it is meant to, sounding in no way analytical or aggressive, but well defined nonetheless. Musicians and singers have a notable amount of air around them, so they take on a singularity, inhabiting their own distinct space. This is not just the character of the disc itself, but rather the way the EVo 200.2 helps to reproduce it. Tube amps often have the ease, but they can congeal the soundfield. Solid-state amps can resolve, but the sound can lack seduction. With the EVo 200.2, the music is easy, sweet and defined -- the events take center stage, not just the qualities of the sound produced.

I don't want to travel too far into the metaphysical reaches of audio reviewing, so I will also say that the EVo 200.2 has very delicate highs, non-digital if that's more descriptive. The amp's midrange has no added sweetness -- here is where you'll know there are no tubes at work -- but this adds to the unique sound of the amp. Vocals have no added chestiness or body, which can often make them sound more palpable, but with the EVo 200.2, their outlines are well drawn, so there's no ghostly disembodiment about. The EVo 200.2's bass is good overall, but it runs out of steam at its lowest reaches. It doesn't have mega solid-state -- Simaudio, Levinson or Krell -- slam or power, but it does have some "pop," some impact, and these make it satisfying nonetheless. Driving the Wilson WATT/Puppy 6es, the EVo 200.2 can punch you in the stomach when called on to do so -- as is the case with "Hard Up Case" from Walter Becker's 11 Tracks of Whack [Giant 24579]. With "Mobile Home" from The Presidents of the United States of America's Pure Frosting [Columbia CK 69201], I can feel the thump in my abdomen -- and even a little lower. If you've ever stood in front of the PA stack at the union on a Friday night, you know what I mean.

But what I keep coming back to with this amp is that connection to SET sound, the subtlety and nuance, that "event" thing. A few months ago I reviewed the Guy Van Duser and Billy Novick disc Lovely Sunday Afternoon [Daring Records 25101], a calm, soothing collection of songs performed on guitar and clarinet. With the EVo 200.2 in my system, the laid-back vibe of this CD is preserved -- clarinet on "New Orleans Farewell" waaaay behind the speakers, and even the front wall of my listening room, the light strumming of the guitar delicately captured. Everything is clean and clear, but not in any etched or hyped way, which heightens the sense that every musical element is being handled on its own. Involvement is greatly increased, mostly due to the how this amp serves the music. People who like a darker, tubier view of things will probably think the EVo 200.2 is a tad lean, while solid-staters will believe the amp lacks authority. But somewhere in between these two extremes is where the truth about the EVo 200.2 lies -- and why it sounds so seductive.

Comparison

What comparison? I wondered when the Bel Canto amp arrived. The EVo 200.2 is not solid state or tubed, so I had nothing like it on hand. Luckily, the amp's sound helped me out. Some of you reading this next statement may find it to be hyperbole, but the EVo 200.2 sounds more like my reference Lamm ML2s than any other amp I've heard. That's right -- the $30k, SET, Reviewers' Choice Lamm ML2 monoblocks. But don't get the wrong idea here -- the EVo 200.2 and ML2s are not sonic twins; however, there are some obvious similarities and differences.

First and foremost, both amps are magical in ways that other amps are not -- defined, easy, involving, musical. The Lamms have the tube palpability and bloom that the EVo 200.2 lacks, so they sound more full and sweet overall. They also have more growling bass -- up to the volume level at which they run out of steam. There's also greater meat to their treble, more bite to brass and steeliness to cymbals and guitar strings, and just as much air. But the EVo 200.2 will play louder for sure, and it also handles the musical events with as much care, creating a sonic landscape that is only slightly less involving than that of the Lamms, and of no consequential difference unless you compare the two side by side. Will some buyers of the Lamms consider the EVo 200.2 instead? Probably not -- different sound and ownership league. But if you've longed for some of the traits I describe but have needed a reasonable amount of power too (and haven't wanted to bother with tubes), you should give the EVo 200.2 a serious listen. It's worth your time.

Conclusion

The Bel Canto EVo 200.2 amplifier is a significant product that breaks down the barriers via new technology, in its case the use of Tripath digital technology. I still like tubes, and my Lamm ML2 SET amps especially, but I could easily settle down with the EVo 200.2 (or perhaps a pair running in mono) for the long haul. There's so much to admire -- easy, involving sound with delicate highs, good bass, and that almost indescribable handling of individual notes that makes SET fans swoon. Add all this to an amplifier that draws little power, runs cool, has power output to drive most speakers, and costs under $2500, and you have a sure Reviewers' Choice product.

And who knows where this new technology will go from here? Bel Canto has already released two more models with more channels, and other companies have announced soon-to-be-available amplifiers built around similar circuitry. Perhaps the true promise of digital technology on sound is just being determined.

...Marc Mickelson
marc@soundstage.com

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