Jadis Defy-7 Mk.II power amplifier Page 2
Notwithstanding the printed circuit board layout, the ground is firmly defined for both channels by a hardwired stack of solder tags securely bolted together. All the main ground lines, speaker transformer, supply chassis, pcb, and other ground lines assemble here in recognition of the importance of this central star-ground concept.
The Defy-7 was run in for a few days after delivery. Once burned in, 15 minutes' warmup from cold seemed sufficient for it to reach a good operating plateau. Its sound grows noticeably better in the first five minutes after turn-on.
Auditioning the Defy-7 was a joy. This power amplifier can thunder with the best of them; musically, it has a heart of gold. It wasn't wholly perfect, however, demonstrating detectable deviations from neutrality at several points.
But to begin with, it's important that I convey an impression of the overall effectthe Defy-7's major achievement. This unit conveyed authority and massive reserves of power, a rare occurrence among tube amplifiers; when called upon to deliver them, it performed without a trace of indecision, strain, unmusical hardening, or concomitant shifts in tonal balance. No matter how hard I tried to back this amplifier against its performance wall, it continued to deliver until the peak sound levels reached were beyond need or reason. The fact that it was able to do so, into such a tough load as the Wilson WATT 3/Puppy 2, came as a welcome surprise. I have never heard these speakers play so loud so gracefully.
I swear that the Defy-7 sounded more like 300Wpc than the 100Wpc claimed. I had been warned it would drive the Wilson system well, but the loudness reached in my own room was the proof. A welcome and highly favorable aspect of the Defy-7 was its almost complete lack of enharmonic coloration and an absence of the usual "amplifier" hardness, compression, and tonal thinning. It sounded rich and sweet, but naturally so, with no attendant loss of transients, or of speed or sparkle in the treble.
High-end power amplifiers often sound generally admirable, yet may leave one restless, either because of a lack of dynamic contrast, or perhapseven worsea lack of rhythm or pace. Harmonic structures may sound thinner, more clinical, cold, and hard than reality. Such unwelcome sound, unfortunately characteristic of much audio equipment, can be unkind to digital sources, exaggerating their defects and militating against a natural, harmonious sound.
Listener fatigue with the Jadis was very low; in fact, both digital sources and those CDs which had previously given trouble in this respect sounded significantly "nicer" when played through the Defy-7. It sounded full, generous, and warmhearted, at the same time convincing by virtue of its dynamic authority, resolution, clarity, and superb integration.
With this strong inner purity, it also sounded simple and direct; transients were conveyed with liveliness and speed, but with no hardness or aggression. The sense of natural rhythm and excitement was also strongly conveyed with all kinds of music.
Examining my notes, I find that in fact, the Defy-7 attracted very little criticism. If compared with a Meridian 605, it is a little "slower" and more relaxed rhythmically; if compared with a big Krell such as the MDA-300 monoblock, then its bass does not quite convey the integrated power and outright high-current slam. Conversely, I found that it set the highest standards for transparency. Ally this with the very good stereo focus and excellent stage width, and you have a glorious soundstagespacious, open, detailedone which contains a wealth of perspective information. It was not just the very high level of detail which helped to maintain interestit was the way that detail was supported in that lush, ambient soundfield. Low-level detail was also very good, the high clarity preserved over the whole dynamic range.
Dynamics were expressive in a natural sense, and made many solid-state amplifiers sound somewhat obstructed and compressed by comparison. As one listener remarked, the Defy-7 made other amplifiers sound "uptight."
The midrange was exemplary (a Jadis hallmark, this), with particularly revealing levels of accuracy on acoustic guitar, mandolin, and vocals. Yet the treble was almost in the same class. When I reviewed the big JA 200 monoblock some years ago, I remember criticizing its treble range for a lack of integration and a noted "carelessness." How times have changed! As expressed in the Defy-7, the Jadis treble was superbly coherent and integrated: grainless, well-balanced, detailed, unforced, and sparklingly natural.
In case you're worried, nothe bass did not get left behind. It marked an advance over the Audio Research D400 (remarkable in itself), building upon that achievement with a substantial level of slam and neutrality. The Defy-7's bass was big and tuneful, its high level of definition ensuring good articulation on complex bass lines.
Some amplifiers show an inclination toward a specific class of program or system; for example, the D400 sounded more comfortable on bigger systems and was better suited to classical music, while the agility of the Meridian 605 is often heard at its best on smaller, faster systems with rock or jazz. The Defy-7, however, showed no such bias. While its "classical" musical character lent itself to the natural-sounding replay of natural instruments and voices in real acoustic environments, I found that I enjoyed it just as much on rock as on classical material.
Seductive on intimate works, it was never fainthearted when called upon to deliver the big bangs. These were truly impressive, yet were never coarse or blocked.
The Defy-7 is a mature end-product of the Jadis design philosophyone which attains a powerful balance of tolerant matching, pure fidelity, outright performance, and effective price. Moreover, that special Jadis midrange performance has been expanded to encompass the bass and the treble.
The marvelous sound delivered by this remarkable tubed stereo amplifier puts it in the front line, up there with the world's best amplifiers. I hesitate to say it is "the best," as such a distinction also requires very high standards of load driving, build quality, and longevity.
The massive strengths of the Defy-7 are its natural, transparent, unfailingly musical sound coupled with an astonishing ability to play loud even into such difficult loads such as the WATT 3/Puppy 2. The synergy exhibited between the WATTs and the Jadis is quite a phenomenon, though other speakers also showed the very high quality of this tubed power amplifier.
A natural, liquid sound is a top priority, of course, with a tube amplifier, but one also often has to consider compromises in accuracy and control at the frequency extremes. This is not so with the Defy-7. The subjective performance at the frequency extremes leave very little to be desired, and could not be considered compromised.
The laboratory results show how little we really know about the science of sound quality. We would like those comforting classic lab results to correspond more closely to the listening experience, but even now, after some 45 years of high-fidelity development, we are only a little wiser. There is insufficient space here to elaborate further except to say that the behavior of the Jadis appears to be closer to that of the human ear than that of a piece of lab test gear.
This amplifier is well finished and looks the part. Conversely, the internal build quality in places verges on the amateurish. The Defy-7 is designed sufficiently conservatively to enjoy a much higher reliability than earlier Jadis models, but only time will tell. Certainly Jadis could try harder with the interior design.
Nevertheless, I am favorably disposed toward the Defy-7. It worked flawlessly over the extended test period, giving much musical pleasure. Given the inevitable health warning valid for almost all high-power tubed power amps, I can confidently recommend this true audiophile design. Despite the very minor deviations itemized above, I have no hesitation in placing the Defy-7 high in the list of my favorite power amplifiers, and regard it as a reference in its power and price class. I defysorry, I can't resist the pun!anyone to dislike this amplifier (footnote 1).
Footnote 1: Since MC finished his review, we have been informed that the Defy-7s being imported to the US by Fanfare have been improved upon in minor ways. Jack English is currently working on a "Follow-Up" review, therefore.John Atkinson