What a thankless task! No, not reviewing audio equipment (though the case could be made). I'm talking about preamplification in the digital age: who needs it? The EAD DSP 9000 MK3 digital processor I'm using includes an ingenious full-resolution digital-domain volume control accessible by remote control.
How important is the use of balanced circuit typology in the design of preamplifiers and power amplifiers? Ask the top audio designers (I didn't, but just play along, okay?) and you'll get a wide variety of opinions. Some reject the balanced approach outright, arguing that it represents a needless duplication of circuit components, and that better results can be achieved if the same attention and resources are devoted to perfecting a single-ended circuit. In his provocatively titled article "Balance: Benefit or Bluff?" (Stereophile, November 1994, p.77), Martin Colloms questioned the advantages of balanced designs, suggesting that while the results may be better in certain respects (eg, noise level), the reproduced sound may suffer in other, perhaps more important ways (eg, rhythm and dynamics).
For those of us who have succumbed to the enticements of surround-sound for music, Audio Research's SDP1 is both vindication and cause for rejoicing: vindication because surround-sound's acceptance by such an ultraconservative, uncompromising company as ARC will give it a respectability in the high-end community that it never enjoyed before, and cause for rejoicing because someone has finally done music surround right.
I had been sent a sample of the Woodside SC26 tube preamplifier during my June 1994 review of Woodside's 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.
Last September, in Vol.15 No.9, I started my quest for the Ultimate Kilobuck Tube Amp with reviews of the $995 Panor/Dynaco ST70-II and the $1695 Nobis Cantabile. While neither really fit the bill—the Dynaco fell a bit short in terms of sonics, while the Nobis was priced a bit higher than a thou—they got me thinking of the Ultimate Kilobuck Tube Preamp. Because the greatest amp in the world can only sound as good as whatever drives it, and there's no sense looking for a kick-ass affordable tube amp if you're going to play Scrooge McDuck when it comes to the preamplifier.
In its comparatively few years in the marketplace, the line-level preamplifier appears to have established commercial parity with its full-function big brother. That this was inevitable was clear as far back as the mid-'80s. The advent of the CD and the proliferation of digital sources argued for a modular approach to preamp design. In such an environment, line-level sources (eg, DAT, CD, even analog tape) deserve special attention.
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. 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."
I must admit that, for a long time, I found it difficult to accept the idea that a major portion of one's audio budget should be spent on the preamplifier. Speakers, yesthey produce the sound; amps drive the speakers, so they're important. And source components? Well, everyone knows it's garbage in/garbage out. But a preamp? Even the name suggests something that's not quite the real thing, like pre-school, pre-med, or premature. Unlike amplifiers, they don't have to contend with loads that sometimes approach a short circuit, and heat dissipation is not normally a problem. What's the big deal?
A "CD processor," is how I distinctly heard Cary Audio's Dennis Had describe it. The venue was Stereophile's High End Hi-Fi Show in New York last April. Nothing really unusual in today's digital marketplace, I thought to myself, though a bit out of character for a company dedicated to vacuum-tube technology. But wait a minute. Dennis had described it as an analog CD processor. Analog!? Well, yes, the unit processes the analog signal from a CD player.
The name "Audio Research" will be familiar to many readers of this magazine. It belongs on the list of that select group of manufacturers who continue to offer the audiophile and music lover equipment which enables him or her to truly enjoy the muse. With equipment of this caliber, one is no longer caught up in the anxiety-inducing process of listening to (evaluating) the equipment used in the presentation of the music. Instead, the listener can focus attention on the much more important message uncovered in the music via the performance and conveyed through the network of transducers, cables, tubes or FETs, more cables, more tubes or FETs, and more transducers, to the brain. If this process has been successful and our sensitivities heightened, our souls will be touched.
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.
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.
If I had to pick one amplifier designer as having had the greatest continuing influence on the high-end market, as much as I admire John Curl, Audio Research's Bill Johnson, and Krell's Dan D'Agostino, the name of David Hafler inexorably springs to mind. Not because he challenged the very frontiers of hi-fi sound, but because he combined a fertile, creative mind (footnote 1) with a need to bring good sound to as wide an audience as possible, both by making his products relatively inexpensive and by making them available as kits. (The Major Armstrong Foundation apparently agrees with methey presented David with their "Man of High Fidelity" award at the summer 1988 CES.) It remains to be seen if the Hafler company will continue in this tradition, now that David has sold it to Rockford-Fosgate. But there is no doubt that many audiophiles were first made aware of the possibilities of high-end sound by Hafler products in the late '70s, and by Dynaco in the '60s.
Following the introduction of their very expensive, tube/FET hybrid SP11 preamplifier, there were rumors that Audio Research was working on a hybrid tube/transistor preamplifier targeted to cost less than $2000. The rumors were confirmed when ARC showed a black-and-white photo of the SP9 at the 1987 Winter CES. Obviously, like all magazines, we were impatient to receive a review sample, but the first review of the SP9 actually appeared in the summer '87 issue of Peter Moncrieff's IAR Hotline. Peter's review was almost intemperately enthusiastic, comparing the SP9 positively with early samples of the SP11 and suggesting that its sound quality was considerably better than would be expected from its $1695 asking price. Naturally, we were anticipating good things when our review sample arrived in Santa Fe in late July.