Solid State Power Amp Reviews

I am obliged to begin this review of First Watt's new stereo power amplifier, the SIT-3, with an explanation of how I believe a power amplifier should be reviewed. Why? Because the 18Wpc SIT-3 is a unique and historically important design that can't be wired up to just any loudspeaker and then critiqued on the basis of its bass power, treble brightness, or midrange acuity.

Japanese audiophiles venerate American high-end audio components, paying huge sums for vintage Marantz tube amplifiers, racks of Levinson ML-2s, and early Audio Research tube preamplifiers. The balance of trade, at the high end anyway, hasn't been reciprocated: Japanese high-end amplifiers and preamplifiers have not received as positive a reception in the US. Perhaps it was a matter of styling, but the sonics of the Sony Esprit line and the class-A Stax amplifiers did not receive the following they might have, had the products been American.

I am finding hard to grasp that it is almost 50 years since I first went to a hi-fi show. That show, held at London's Olympia exhibition center, was notable both for Yamaha's launch of a loudspeaker with a speaker diaphragm shaped like a human ear, and for being the first time I saw the drop-dead gorgeous Transcriptors Hydraulic Reference turntable, which was later featured in the film A Clockwork Orange. The most recent show I attended was AXPONA, held last April in the Chicago suburb of Schaumburg. There I saw no ear-shaped drive-units, but the final room I visited featured sound that the 1969 me could have only fantasized about.

Founded by Nelson Pass in 1974, Threshold is one of those companies audiophiles tend to take for granted. Best known for the much-imitated Stasis (sliding bias) amplifier designs, Threshold became one of the industry leaders during the early 1980s. Since then, they've been upstaged somewhat by such rivals as Krell and Mark Levinson, and the public's impression of the company's stability wasn't helped by the departure of several of its principals, including Nelson Pass.

Not everyone needs a power amplifier that can deliver 888W RMS into 8 ohms or 1776W into 4 ohms. You could say that no one needs one of these—or two, if you want to listen in stereo. Most household AC systems can't even provide enough current to deliver all that power. But Simaudio does build Moon 888 monoblocks, and people do buy them, whether or not they need an amp that weighs about 250 lb each and costs $118,888/pair.

When it comes to amplifiers, ya gotcher tubes, yer solid-states, and yer hybrids. Although amplifier manufacturers would have you believe otherwise, the majority of designs within each category are variations on a few fairly-well-known themes. Everyone agrees that the power supply is extremely important. Most designers try to obtain the amplifier's desired frequency response and distortion characteristics with a minimum of negative feedback. It's also agreed—at least among designers of solid-state amps—that the ability to drive a variety of speakers, including those that present a low-impedance and/or reactive load, is an important priority.

On the second morning of a recent audio show, I walked into the exhibit room of Bricasti Design.

"How about some Mahler?" asked cofounder and designer Brian Zolner.

"Oh God. Not at 10am!"