You are reading the older HTML site Positive Feedback ISSUE november/december 2007
conrad-johnson ART (Anniversary Reference Triode) Series 3 preamplifier - Rebirth of a Classic as reviewed Myles B. Astor
The original ART
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Ever notice how high-end audio components come and go like restaurants? Hot one year; gone the next. It's only the crème-de-la crème, those ultimate high-end audio components such as conrad-johnson's ART tube preamplifier (Anniversary Reference Triode) that stand the test of time. While the original ART Series 1 set the Gold standard for timbral accuracy, microdynamic attack and intra-note silence, soundstaging and imaging, the latest Series 3 edition breaks down many of the long hallowed boundaries between reproduced and live music. A Little History Here's a quick refresher for Positive Feedback Online readers unfamiliar with the development and history of conrad-johnson's ART preamplifier. Originally a "laboratory" research tool, ART designers Bill Conrad and Lew Johnson aka conrad-johnson, "never in their wildest dreams ever contemplating releasing this preamplifier to the public because the cost in parts alone was astronomical." Eventually though, Conrad and Johnson decided to on the anniversary of their companies 20th year in business, "share this design with a few people" and release a limited edition run of 250 ART Series 1 preamplifiers. With only three ARTs left looking for a home, Johnson, initially skeptical whether they would sell all 250 units, now confesses "he's sorry to see them all gone!" When the ART Series 1 first shipped in January, 1997, the preamplifier's price tag was an almost unheard of $13,500; sometime thereafter, the price rose to $15,000. Current list price on the new ART Series 3 is $25,000 but as we shall see, parts quality makes up a large percentage of the unit's price! In fact, conrad-johnson was very early in the game, onto the relationship between parts quality and sound quality. That philosophy was first implemented in the now Jurassic Premier 2 preamplifier, where conrad-johnson bypassed every electrolytic capacitor in the signal path. Subsequently, conrad-johnson replaced all the electrolytic capacitors in the signal path with their own specially designed polystyrene capacitors in the Premier 3 preamplifier. The final step in the process, and this was embodied in the original ART Series 1, was completely eliminating all electrolytic capacitors from the signal path and power supply. Nor are other parts quality neglected; a quick scan of the circuit board finds Vishay resistors ($15 a pop) liberally sprinkled thoughout the circuit board. To this day, conrad-johnson has never deviated from their basic philosophy and it forms the foundation for the ART series 3 revision. Another new design feature implemented in the ART Series 1 was the use of paralled sections of small triodes to form a "composite circuit" or "supertriode." This "supertriode" allowed Conrad and Johnson to first dispense with the traditional cathode follower/buffer stage and all its drawbacks. Another benefit to paralleling together the five sections of a 6922 dual triode (a high transconductance, low mu or high load, low source impedance tube) is a reduction in the preamplifier's output impedance; this allows the ART to drive long interconnect runs (by comparison, the circuit utilizing a 12AX7 would have an output impedance of 3 to 4000 ohms). Finally, this "supertriode" configuration also dropped the preamplifier's noise floor by 6dB. Revisionist History Conrad-johnson announced the first update to their flagship preamplifier in late 2000 or early 2001 (approximately five years after the initial release). In the ART Series 2 (this update is no longer available), conrad-johnson replaced the unit's stock input and output jacks with substantially more expensive oxygen-free copper, gold plated input and output connectors. Other internal changes included new, higher quality power supply resistors and doubling up the thickness of the finely stranded monofilament silver hookup wire. The introduction of the ART Series 3 happens to, but Lew Johnson "assures me that it's pure coincidence," correspond with conrad-johnson's 30th and the ART's 10th anniversary. The first and most significant change, both sonically and cost wise in the ART Series 3, is the implementation of conrad-johnson's hot, new Teflon film capacitors. (Basically everything but the metal work is thrown away in the Series 1 to 3 update.) In large part, conrad-johnson's switching from polystyrene to Teflon capacitors was precipitated by the shuttering of the two remaining factories left in world producing audiograde polystyrene film (in Germany and the Far East). Armed with this knowledge, conrad-johnson stockpiled roughly $500,000 worth of polystyrene capacitors; their suppliers also stocked up on materials so conrad-johnson ended up with about 5 years worth of polystyrene capacitors. But eventually the day of reckoning came—and conrad-johnson faced a dilemma. They could return to using what they felt were inferior polypropylene capacitors and maintaining the unit's price—or switching to their current state-of-the-art Teflon capacitors and increasing the price of the units. (conrad-johnson also evaluated other types of capacitors such as oil filled but didn't find them better, much less equal to what their current polystyrene capacitors). The good news first: conrad-johnson, working in concert with their capacitor supplier, developed a way of constructing and winding a 2 µF/250 V rated, Teflon capacitor. Now for the bad news: these larger value Teflon capacitors are hideously expensive costing conrad-johnson around $240 apiece. With 32 Teflon capacitors in each ART, I'll leave the math up the readers. Johnson feels the new Teflon series capacitors significantly improve the "ART Series 3 top end, focus, temporal aspects and resolution." Another significant change in the ART Series 3 is a redesign of the unit's power supply. In the ART Series 1 and 2, conrad-johnson cascaded two power supply regulators to prevent AC power line noise from reaching the critical active circuitry. Conrad-johnson found in the course of designing their CT5 and ACT 2 Series 2 preamplifiers that they could eliminate one of the two power supply regulators, thus effectively doubling the preamplifier's power supply reservoir. This change was also incorporated in the ART Series 3 and Johnson says results "an improved low frequency performance and overload characteristics in the ART Series 3." Finally, Conrad and Johnson made some additional revisions to the ART's circuitry resulting in a lower noise floor as well as changing the values in other parts of the circuit such as increasing the size of the reverse filtering caps in the audio circuits by a factor of ten. Present Day History Realizing the preamplifier's state-of-the-art performance requires a pinch of patience as the ART Series 3 thirty-two Teflon capacitors take an eternity to burn-in (putting some high-end audio cables to shame). Designer Johnson cautions against jumping to any conclusions about the preamplifier's sound until the unit has 300 hours of playing under its belt. In my experience, 300 hours is a touch conservative; 400 hours is perhaps a more realistic figure. So plug in the CD player, insert a disc, push play and repeat and be prepared to wait a couple of weeks for the unit to change from an ugly ducking into a swan (actually the unit sound pretty good out of the box; it just gets better and better with time). As the ART Series 3 burns-in, expect to initially hear changes in frequency extension, then a filling out of the midrange frequencies and finally increased dynamic range. Two other quick installation notes. First, don't forget to remove the four circuit board lock down screws located on the bottom of each chassis before permanently placing the ART. Second, make sure to compensate for the fact that the ART, because of its single gain stage, inverts absolute phase (this is clearly explained in the owner's manual). That's not quite the end of the set-up saga. More than any other state-of-the-art high-end audio component in recent memory, the present day ART Series 3 must be surrounded by the best front-end components, amplifier (s), speakers and cables. The preamplifier's neutrality and incredible low level resolution ruthlessly exposes colorations lurking elsewhere in the audio playback chain. Differences between EMI, RCA, Mercury and Decca recordings—or original vinyl pressing and their reissues, are instantly revealed. When paired with conrad-johnson's outstanding 140 wpc Premier 140 stereo tube amplifier, the ART Series 3's vastly improved and extended frequency extremes, greater low level information retrieval, untube-like transient attack and an uncanny freedom from overload characteristics under duress were unmistakable. Yet, the system still leaned to the dark side.
My gut feeling told me that the ART Series 3 was capable of even greater things. Greater openness. Greater transparency. Greater dynamics. Not to get ahead of myself, but the single biggest improvement occurred when my reference Premier 140s was supplanted by conrad-johnson's newest LP-140 M monoblock tube amplifiers. Frequency extremes were more extended; upper octaves in particular, were delicately rendered. The soft end of the dynamic spectrum was softer; the forte end more bombastic. The improved dynamic envelope necessitated a relentless raising and lowering of the volume levels. Transparency, particularly in the back of the stage, was vastly improved and the Summit electrostatics never sounded more transparent. The end result: an even greater appreciation of just what Conrad and Johnson wrought in the latest Series 3 update. Among those capabilities is an uncanny ability to beak the sonic barrier between reproduced and live music. The ability to give more often than not, a shockingly real glimpse of the recording event. The personification of what constitutes a "musical" component—not something so technicolored that one walks away from a listening session thinking if only music sounded like that! No doubt that's putting my neck on the chopping block but the ART's combination of new found tonal purity combined with its lack of distortion, extension at the frequency extremes, quietness and increased low level resolution reveal a wealth of new information on LPs. The ART's musicality makes every album a new sensory experience . Take the track Bob and Ray visit "Dr. Ahkbar at the Castle" from Bob and Ray Throw A Stereo Spectacular (RCA LSP-1773). Through the new ART, there's a new found sense of depth, solidity, weight and overall information when Bob and Ray travel across the rickety bridge to the castle, announce their arrival with the big brass knocker and the heavy, wooden door swings open. Soundstaging and imaging—hardly a conrad-johnson weakness—is far better in the newest version of the ART preamplifier. There's a completely new sense of three-dimensional space and solidity when the wine is poured into the glasses—or the glasses are thrown into the fireplace. Duck when Neil streaks your way! Jumping ahead a few tracks to "Bob and Ray: The Thing," there's an eerie ability to perceive the entire arc of the human pendulum from outside one speaker to the outside of the other speaker. The human pendulum's screaming for help (and pain) makes the hair on the back of ones neck rise. Where the newest ART stands alone is in its distinct lack of artificiality. There's no added sheen or hyperdetailed quality to the music. No slight leanness and coldness in the upper midrange particularly apparent on strings. Returning to an album used in the original ART Series 1 provides even greater insight into the improvements wrought in the latest iteration of the ART preamplifier. Take Cowells "Pulse" or Cage's "Third Construction" from the original album entitled Pulse: Music for Percussion and Strings (New World Record 319). Two attributes observed in the original review included the ART's tonal purity and low level resolution—in particular the ability to reproduce the ringing, shimmer and three dimensional radiating surface of cymbals—or a stick meeting the wood blocks and their the "cupped" resonating feeling. The latest incarnation of the ART preamplifier takes this album to a new level with even greater upper and lower octave extension, resolution and delicacy, evidenced by the decay time and ability to identify and solidly place every percussion instrument. Instruments have well defined edges, made all that clearer, by a lack of veiling over the stage and between instruments. Percussion instruments are less distorted and lack glare or hardness even with the most demanding transient attack. Even more striking was the ART's ability to reveal difference between tracks and between sides (not only recording but lacquer and pressing related differences). Here the side containing Cage's "Third Construction" (and other tracks) was clearly better sounding side with a greater sense of space, cleaner low end and more dynamics—though the low frequencies could still be a touch cleaner. Upper octaves on "Third Construction"emerge aren't veiled as on the other side and are more delicate and extended. Information buried in the noise floor is now clearly revealed. Or to illustrate the differences between different pressings of the same recording , take Bill Evans last recording for Riverside, Bill Evans Trio at Shellys Manne-Hole (Analogue Productions/Riverside 9487 or OJC-263). The differences between the budget OJC and the newest 45 rpm Hoffman/Gray effort, even after compensated for differing record thicknesses, are even more amplified by the ART Series 3. The AP reissue is oh-so much quieter and transparent. Israel's double bass is more focused, no longer buried in a sea of mud and sounds as if there's another octave of extension (though there may be a touch too much bass on the reissue). Evan's piano on the AP pressing lacks the coldness of the OJC. His piano is richer without being colored and more three-dimensional. The piano is awash in a sea of ambience. On "Swedish Pastry," one can close their eyes and imagine they are being transported back to the club. Larry Bunker's drum emerges from behind a curtain and has a greater sense of body and solidity, speed and timbral information from the lowest to highest octaves. Rewriting History As I concluded in my original 1997 review, "the ART is destined to take its place alongside conrad-johnson's own Premier 1 and 8 amplifiers as classic high-end audio tube designs." Ten years after its release, the ART Series 3, with a revised power supply here, new capacitor there, has clearly superseded the accomplishments of the Premier 1 and 8 amplifiers and remains the Gold standard against which all other high-end preamplifiers must be judged. Soundwise, the ART Series 3 isn't necessarily a radical departure from the sound of the original ART. In many respects, the latest iteration realizes the designer's original musical intent envisioned for the ART Series 1: revealing the minute details of recordings and differences between recordings; achieving a lack of artificiality that distracts the ear from enjoying the music; the ability to render massed strings and wrap them in a envelope of ambient air; and reproducing the soundstaging and instrumental focus captured by each engineers favorite microphoning pattern. The shame of it all is that only three ART Series 3 preamplifiers remain for sale; still all current ART owners should seriously consider updating their units. For those readers who must have the best, check out the new ACT Series 2 preamplifier, conrad-johnson's new stereo "flagship" and most practical embodiment of the musicality achieved in the latest ART Series 3. Myles B. Astor
conrad-johnson ART Series 3 Preamplifier
conrad-johnson design, ltd
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