Tube Preamp Reviews

You know me. I'm not perzackly an audio slut, but I am easy. When Audio Advisor's Wayne Schuurman called me to pitch the Vincent KHV-1pre tube-transistor headphone amplifier, he pretty much had me at "tube" and "headphone." But I wasn't familiar with Vincent Audio.

Whenever an audio high-ender thinks about tubes, he usually thinks about Audio Research. This is only natural, because Audio Research Corporation was almost single-handedly responsible for saving tubes from oblivion in the early '70s when everyone else switched to solid-state. But ARC was soon joined in its heroic endeavor by an upstart company called Conrad-Johnson, which entered the fray in 1977 with its PV-1 preamp, priced at an affordable (even then) $500.

As I write, it is garage-sale season here again in Santa Fe, and a recent sign near my home advertised "Over 3000 LPs, good condition, low prices." To my surprise, the seller wasn't a yuppie enamored of his new CD player but a true collector discarding the duplicates and dogs from his collection. 30 minutes later, many LPs heavier—including a mint Flanders & Swan At the Drop of a Hat (footnote 1)—and not too many dollars lighter, I returned to a great night's listening courtesy of the black vinyl disc.

I had been sent a sample of the Woodside SC26 tube preamplifier during my June 1994 review of Woodside's MA50">http://www.stereophile.com/tubepoweramps/694wood">MA50 monoblock amplifier (Vol.17 No.6). Although I used a number of preamplifiers during that review, I was most impressed with the MA50s' spacious, three-dimensional soundstage when driven by the SC26. At the time, I had an impression that the SC26's sonics combined a midrange richness with a good dynamic range. Although I had to return the Woodside MA50s to the importer after I reviewed them, I continued listening to the SC26.

I'm not sure what motivated me to read the owner's manual for the Audio Valve Eclipse, but I'm glad I did: As it turns out, this line-level preamplifier has at least one distinctive feature that I would have missed otherwise.

Conrad-Johnson launched the all-tube Premier 7 in 1988 as an all-out sonic assault on the state of the preamplifier art. A great deal has happened since then. For starters, C-J has gotten a great deal of feedback from customers, dealers, and reviewers. None other than J">http://www.stereophile.com/interviews/66">J. Gordon Holt (Stereophile, November 1988, Vol.11 No.11) concluded that: "It appears that nothing which could possibly have improved its sound had been omitted....It is, in fact, about as close as any tubed preamp has come to being perfectly neutral in sound—in nearly all respects." In the now-defunct Sounds Like... (issue 3), Sam Burstein concluded that "It is, with certain reservations, absolutely delightful to one's musical senses." And, speaking of absolutes, even Harry Pearson gave the Premier 7 a rave in the first round of his preamplifier survey (TAS, issue 58). As icing on the cake, John Atkinson (Stereophile, Vol.12 No.8) concluded that the 7 had "the requisite degree of sonic magic to make it a Class A recommended preamplifier."

Just about any consumer-electronics product that needs to generate voltage gain can be made with a vacuum tube. It isn't hard to do. It's no big deal.