Tube Preamp Reviews

I've long admired Vacuum Tube Logic's line of amplifiers and preamplifiers. Owners Luke">http://www.stereophile.com/interviews/153">Luke Manley and his wife Bea">http://www.stereophile.com/interviews/607vtl">Bea Lam routinely appear at the Consumer Electronics and Home Entertainment shows with luxurious, microprocessor-controlled tube gear, soothing new music, good-sounding rooms, and a friendly, unhurried manner. Their show setups are dialed in so well that I often find myself taking refuge there, sitting and listening for hours with other Stereophile writers.

Everybody loves a bargain. No—make that: Most people love a bargain. Some just want the best, and they don't care about the cost. Some even distrust and reject out of hand any product that's not expensive enough. If you're one of these people, you might as well stop reading this review right now—the PrimaLuna ProLogue Three and ProLogue Seven are not for you. $1395 for a tube preamp? $2695 for a pair of 70Wpc tube monoblocks equipped with four KT88 tubes each? Must be based on old designs in the public domain using cheap parts carelessly assembled...

In any category of product or service, there is a gold standard—one company that epitomizes the best in its field of endeavor. Consider the Rolex watch, the Ferrari sports car, the Steinway piano, the Dunhill pipe. All of these artisanal manufacturers have spent decades, even centuries, earning their names' cachet with their histories of consistent excellence. While high-end audio boasts no names with a 60-year pedigree, such as Ferrari's—much less Steinway & Sons' +150 years—there is one firm whose storied past stretches back to the very emergence of the concept of high-end audio itself: Audio Research Corporation.

"It's a series of tubes."—Senator Ted Stevens (R-AK), explaining how the Internet works

RCA's time-honored 6SN7 may be the coolest tube of all. The octal-based dual-triode has its own Wikipedia entry—something not even the 2A3 or 300B can boast—along with its own websitehttp://www.6SN7.com">website;. The 6SN7 is chunky, rugged, and handsome. Best of all, it's available, probably because people keep coming up with very good uses for it. In that sense, the 6SN7 is the Campbell's Cream of Mushroom Soup of the tube world.

If you review hi-fi long enough, you get to the point where you've heard it all before. Actually, there are several versions of that point: One is where you've heard all the claims before, and the other is where you could have sworn you've actually heard this component before.

My opinions keep changing—more evidence of life before death, I suppose—including my thoughts on audio-system hierarchies. I used to think that preamps were among the most sonically influential components, certainly more so than power amplifiers. I'm not so sure anymore (footnote 1).