Tube Preamp Reviews

The L2 Reference sits at the top of Lamm Industries' preamplifier line. According to the manual, its "unique" circuitry uses specially selected, superlinear, high-voltage MOSFET transistors that ensure class-A operation from input to output, with no overall negative feedback at any stage. All stages, including the high-current output buffers, are single-ended.

As part of my employer's never-ending attempts to transform me from an engineer into a manager, I am constantly being sent to seminars and courses, some of which are eminently practical—like "Managers and the Law," which taught us how to avoid getting ourselves and our company sued. Others are more esoteric, like a recent seminar on "paradigm shifts." A paradigm shift, we were told, is a fundamental change in the way we look at things, arising from a change in a belief so inherent that it's unconscious.

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.

It's a reviewer's privilege to be able to switch back and forth between tube and solid-state gear (or combinations thereof) as the mood or the assignment moves him. Still, I find I'm inevitably drawn back to the Epicurean delights of triode tube gear. When done right, there's an alluring musicality to it, like the breath of life. However, in any tube vs solid-state contest, the relative tradeoffs between tone and resolution—sweetness and articulation, euphony and frequency extension—must be taken into consideration.

Audio Research's first 21st-century, audiophile-quality line-stage preamplifier combines retro-tech vacuum-tube amplification and power-supply circuitry with innovative, remote-controlled gain, balance, tape monitoring, and signal routing. The price is also 21st-century: $9995. As in ARC's Reference phono section, the Reference Two's pair of vertically mounted circuit boards results in a single, relatively tall chassis.

This is an era in which products and websites are "launched," but in the past two years Herron Audio has sort of oozed its way into the public ear. With little visible promotion or splashy advertising, Herron is now spoken of within an ever-widening audiophile circle.

We thought Audio Research's previous-model SP-2C (footnote 1) was excellent, but this is even better—the closest thing available, in fact, to the ideal straight wire with gain. Our sample had a minor glitch—there was a slight "plop" if you rotated the tone controls rapidly—but we could find nothing else about it to criticize. Currently, by far the best preamplifier than money can buy. And would you believe it uses tubes (at reduced heater voltage, for extended life and cooler operation)!