Tube Preamp Reviews

Many tubed preamps can be described as being somewhere on the warm, musical, rich side of neutral. The 7A certainly isn't one of them. If anything, it sounds slightly analytical, favoring accuracy over euphonic colorations. Once again, what I heard through the 7A was very much what JA heard through the original 7. The midrange was phenomenally clean and detailed for a tubed product. With relatively simple music without a great deal going on, every little nuance is laid bare. A good example is Marianne Faithfull's Greatest Hits (London PS 547), which the 7A dissected surgically. Unfortunately, a lot here is better off hidden. Any trace of the 7's supposed caramel coloration would be greatly appreciated with this recording, but there was none to be found using the 7A.

With more complex material, such as The Art of Noise's The Fon Mixes (China WOL 1023), the 7A's ability to unravel information is uncanny. This two-LP set proudly proclaims: "Cut extra-loud at 45rpm for extra noise." The 7A can handle this with no difficulty. It can play it loudly or softly, in either case continuing to keep every note, voice, and line crystal-clear. There is never any confusion, haze, or muddy loss of information.

Since the 7A's avowed intent is to assault the state of the art, I've elected to judge it accordingly. Using this essentially impossible standard, the 7A's midrange offers unsurpassed articulation, detail resolution, and transient speed. But compared to someone performing in your listening room, the 7A is ever so slightly thin in timbral recreation. This is most obvious with the human voice, as in the Marianne Faithfull or Toto recordings. A better example, with more demanding vocals, is The Manhattan Transfer's stunning remake of "Gloria" from their 1975 debut album (Atlantic SD 18133 0698). While the harmonizing vocals are delineated with marvelous clarity, they fall just short of the timbral richness of a live performance. Honestly, I've just got to get one of the newer Benz Micro or Koetsu cartridges to be sure how much of this thinness is attributable to the preamp.

Treble: JGH was very favorably impressed with the 7's trebles; JA said they "soared"; and HP felt there was a trace of high-treble distortion. C-J itself felt that there may have been some minor treble shorétcomings in the phono stage. Since it's difficult to tell how much different reviewers used the phono inputs, it's impossible to attribute their disagreements solely to the performance of the phono stage. Nonetheless, C-J feels any possible treble shortcomings have been eliminated in the 7A's revised phono circuitry. My own hearing was the limiting factor here, as opposed to any shortcoming in my system or listening room. The latter measures flat well out beyond 20kHz, though I can only affirm that via test instruments. Using the Woodford CD and a Radio Shack spl meter, the 7A was still putting out plenty of energy through my system at 20kHz.

The 7A left me a bit confused about the quality of this extended treble performance. With some recordings I heard a very slight hardness or distortion; with others, I heard nothing wrong. I may have more treble problems with some of my LPs and CDs than I thought, which the C-J let me hear for the first time; or there may be some very minor anomaly in the 7A's treble region. However, the 7A did nothing to further exacerbate already "hot" recordings such as Anita Baker's superb Rapture (Elektra E1 60444). The hot trebles were pretty much as I expected, with no additional exaggeration or distortion. Everything else was wonderful: the big, powerful bass, very wide and stable stage, and first-rate resolution of detail. But Anita's voice could have been just a tad richer and fuller.

Putting It All Together
The 7A was out of my system for a while during the course of its rather lengthy review process. I put it back, along with my reference ARC Classic 150s. Onto the Versa 1.0/Benz combo went Michael Doucet and Beausoleil's Bayou Boogie (Rounder 6015). Unlike much of Beausoleil's earlier work, Bayou Boogie is "electrified." While the music remains predominantly acoustic, with accordions and fiddles, there are amplified instruments as well. This Cajun Zydeco music is wonderfully happy-go-lucky. The performance sounds like something you might hear in a local town hall or VFW building. It's natural, exciting, and carefree. You want to call up some friends to have a party.

The 7A didn't draw attention to itself. The performers were placed precisely on a wide stage, back, between, and well behind the speakers. The timbres of the acoustic instruments were natural; the sonic performance was quick, fast, detailed, clean, distinct, and tight. No matter how complex the music became through the performers' exuberance, it never sounded muddled or confused.

As I shifted my attention away from the music and back toward the equipment, I did feel there was something slightly amiss in the trebles. Triangles, in particular, were just a bit hard, their decay a tad foreshortened; but you really had to listen for these effects to hear them. However, listening to gravelly-voiced guitarist extraordinaire Chris Rea (New Light Through Old Windows, Geffen GHS 24232), the treble was admirable. Various cymbals and bells were clear and quick, with nary a trace of hardness or distortion. No matter how I attempted to resolve the treble issue, I just haven't gotten it done. There may be a mild coloration in the upper reaches; I'm still not certain.

After finishing up some new listening to the phono stage, I went back to the line stage using digital. Since I'd been enthralled with a rave Rolling Stone review by Michael Azerrad, I spent an evening with the latest release from My Bloody Valentine. Azerrad described the music on Loveless (Sire 26759-2) as that which "must signal some sort of impending revolution." He went on to quote Brian Eno as saying Loveless "sets a new standard for pop." My audiophile juices ran even higher—the SPARS code read AAD! I couldn't wait.

Ecch! Forget the treble question. This stuff was dreadful. The music gave me a headache; the sonics were much worse. Actually, the credits told the story on this one: four artists, eighteen engineers and assistant engineers! That's 4½ engineers per artist! Every second of this dreck is processed, manipulated, and screwed up in some way or another. The sounds are distorted, confused, discordant, hard, bright, and unclear. The everywhere guitars are tremelo'd, whammied, vibrato'd, and fuzzed into a hazy, muddy mess. The lightweight, wimpy little Kate-Bush–wannabe vocals just don't fit. There is no attempt whatsoever at recreating any type of soundstage, and there are only bare traces of natural timbres. It is as if the entire recording was made on a cheap tape recorder that was on its deathbed. Still, amid all of this engineering prowess, a relatively natural-sounding drum kit survives. The 7A's ability to unravel and reproduce all of this detail let me hear everything that was going on. If the source is lousy, that's just what you'll hear with the 7A. There is absolutely nothing euphonic about the preamp's presentation. As far as Loveless is concerned, that's too bad.

Maybe I'm a glutton for punishment. The other CD I'd put aside for this particular listening session was from Univers Zero (Heatwave, Cuneiform Rune 9CD). I got this one from Ken Golden at The Laser's Edge, who described UZ as "the chamber ensemble from Hell." Rather than starting at the beginning, I opted instead to begin with "The Funeral Plain," the 20:24-long final track. UZ relies on a musical foundation of traditional acoustic instruments—clarinets, saxophones, violins, violas, pianos, percussion, the human voice—augmented by guitars and synthesizers. When I hear a melody begin, I often try to hum the next note in anticipation of where the music is going. Whew! What an experience with UZ. Many melodic lines seem to end on strange notes—either flat or sour sounds following sweet melodies. It's like biting into a lemon. UZ's moods are dark, foreboding, filled with tension; they made me uncomfortable. Often, I found myself literally sitting on the edge of my seat. This is an experience I normally only have with some form of visual or multi-media event. Listening to this music is similar to becoming absorbed in an Alfred Hitchcock movie. Quite a thrill. Once again, as with every other CD and LP thrown at it, the 7A simply let the music play.

The Ultimate Challenge
John Atkinson, Bob Harley, Tom Norton, and Corey Greenberg—three professional audio critics and one professional audio engineer—happened to be in New York for the Fall 1991 AES convention. They graciously made time in their hectic schedules to pay me a visit. As a group, we spent hour after hour listening to LP after CD after LP. One selection led directly to another. We talked and listened to music! We never bothered discussing equipment. The system consisted of a Benz Micro MC-3, Versa Dynamics Model 1.0, Magnan Type Vi interconnects, Theta Data, Kimber KCAG (as a digital cable), Theta DS Pro Generation II, bi-wired ARC LitzLine 2 speaker cables, ProAc Response Threes, dual Tice Power Blocks and Titans, and the Conrad-Johnson Premier 7A preamplifier and Evolution 2000 amplifier. The system just stayed out of the way. The Premier 7A (as well as all of the other equipment in the system) did an admirable job of playing music. This is the ultimate compliment paid to any audio gear.

JE Concludes
First, the design tradeoffs necessitated by the Premier 7A's sole reason for being—sonic performance—make the 7A definitely not the most convenient preamplifier to use. If convenience is high on your agenda, look instead at the remote-controlled preamps from Rowland, Krell, and Berning.

Second, the 7A is extremely expensive, costing $4000 more than the splendid Convergent Audio Technology SL-1 Signature. The lofty price reflects the effort, parts, build quality, and limited production commensurate with such a design.

Third, the 7A is a tubed unit. No matter how carefully you treat any tubed unit, tubes wear out, fail, and have to be replaced. To prolong tube life, the unit cannot be left on all the time like solid-state gear. Every time it's turned on, you'll have to wait a while before the 7A will perform optimally. Changing the 7A's tubes is a pain in the butt. And, while the 7A is remarkably quiet for a tube product, it's noiser than a comparable solid-state design.

The 7A has lost none of the superlative sonic strengths found in the original 7. Like the 7, the 7A offers outstanding soundstaging capabilities; a wonderful ability to recreate air, space, and ambience; and first-rate dynamics that, as a result of the improved power supply, may be actually even better than the 7's. In comparison with musicians performing in my listening room, the 7A has: a trace of tube-like bloom in the bass; a slight loss of timbral richness in the midrange; and a very, very minor occasional hardness in the trebles. Improvements in the phono stage have reduced difficulties in the uppermost frequencies which plagued the original 7. Detail resolution is unsurpassed, as is the recreation of transients.

Following closely in the footsteps of earlier reviewers, I must say that the Conrad-Johnson Premier 7A is one of a handful of truly Class A preamps.