Solid State Power Amp Reviews

Revolutionary is a word that's tossed around all too lightly in the world of audio. The understandable impulse to tout every new development as a quantum leap forward in sound reproduction has made it difficult to sort out the evolutionary from the truly groundbreaking. And there's not that much left to do in amplifier design that is worthy of being described as "revolutionary," or so it seems. Vacuum-tube circuitry has been thoroughly understood since the late 1940s, and 40 years of development of solid-state has rendered it, in its finest implementations, a worthy competitor and alternative to the venerable tube.

As we all know, it's the sound that counts. However, good looks enhance pride of ownership, and Theta Digital's class-AB, 400W Citadel is as handsome a monoblock as these jaded eyes have laid eyes on.

If your audiophile habit goes back more than a couple of decades, you're probably doing a double take looking at the Smart Devices 2X150VT. Looks like a Hafler DH-200, doesn't it? That's because, at its core, a Hafler DH-200 is exactly what it is. Smart Devices doesn't name names in its brochure, but they do say that "You may recognize this amplifier as one of the dominant premium performers of the 1970s and '80s"—a reasonable enough description of the MOSFET-output DH-200, which combined outstanding sound with a very reasonable price—especially if you built the kit.

The word on Bel Canto's upsampling DAC was already out when I visited their room at the 2000 Consumer Electronics Show looking to get one of the first samples. But despite my protestations, all Bel Canto's Mike McCormick wanted to talk about was their company's new digital amp, the eVo 200.2. Sure, there's a future out there in which all sources will be digital and D/A conversion will occur in the speaker (or later?). But today, I see no practical advantage in a digital amplifier with only an analog input. It may be more efficient and it may be new technology, but the amplifier has got to stand on the same footing as any analog design and justify its existence by the way it sounds. The eVo did make a good case for itself at the demo, so I signed up to get one for review.

I've been attending the annual Consumer Electronics Show for years, and usually come away with the impression that there are too many "me-too" products. I see a numbing similarity of approach of manufacturers within a chosen discipline: solid-state power amps in black and silver bristling with heatsinks, single-ended triode amps with their glow reflecting from bronze or wood panels, MCPU/DSP-centered devices with sleek, flat cases and intimidating remote controls, etc.

Back in 1992, Robert Harley's Stereophile review of the McCormack DNA-1 and Parasound HCA-2200 amplifiers (April 1992, Vol.15 No.4) and the accompanying technical measurements piqued my interest. So, with great curiosity, I arranged to borrow a DNA-1 to audition, along with competitive amps from Aragon, Bryston, and PS Audio. They were all a leap ahead of my Adcom GFA-555, but it took an act of great courage to accept that, despite its less-than-stellar measured performance, the DNA-1 was my favorite. The bottom line was that the DNA-1 excelled at driving my Apogee Duettas to make lively and harmonically pure sounds. I bought my McCormack DNA-1 amplifier before I began reviewing equipment for Stereophile, and it still occupies an honored place in my system.

With its latest series of FPB (Full Power Balanced) amplifiers, Krell is taking careful aim at the seam between classic high-power two-channel systems and quality multi-channel installations where sound is yet paramount. Nevertheless, Krell founder Dan D'Agostino was adamant: Krell's Class A components were designed for music playback. "I'm a purist, like you, Jonathan!" he told me.