Manley StingRay Integrated Amplifier

“Starting with the lower octaves, this gutsy little amp delivered firm, extended bass, that sounded “real.” While many amplifiers deliver copious quantities of bass, few of them render sound like the actual bass instruments they’re trying to reproduce.”

Under the leadership of CEO, Eve Anna Manley, working in concert with her astute team of engineers, Manley Labs has come up with a unique integrated tube amplifier, that physically mimics the shape of the aquatic sea creature—the stingray. The amplifier is unique both in its attractive styling and in certain aspects of its design and component parts.

First, I must tell you that although the Stingray was designed by a woman, there is a certain machismo to its appeal that is undeniable. No, it’s not a super-charged Corvette, but under its stainless steel “hood,” lies a little “engine,” that COULD (and DID)! As it happens, the unusual dimensions of the chassis and the layout of the components were initially chosen to optimize its performance.

Let me assure you, there is nothing fishy about the Stingray. I hooked it up to my Eminent Technology LFT-8a speakers (83 dB/W/m), which I didn’t even expect it to drive successfully, and I must say that at moderate volume levels the amp performed like a champion.

Manley says the secret’s in a new output transformer design, which was enthusiastically conceived by “Hutch” Hutchison and Michael Hunter. Armed with an extensive technical library and on-premises transformer winding facilities, they returned to more traditional thinking, but with a few clever twists. Measuring, listening, testing and tuning led to a decision to replace the venerable 15-year-old input stage with an innovative and fresh contribution from Paul Fargo. Separate left and right silver-contact selector switches (for the four stereo line inputs) deliver the music signal to premium Noble® balance and volume controls before hitting the first 12AT7WA input tubes. In effect, this is a very high quality passive preamplifier

Following the 6414 driver/phase splitter, the trusty EL84 output stage (four tubes per channel) yields 50 Wpc of Ultra-Linear push-pull power. However it can be (factory) strapped for Triode operation which yields 25 Wpc. Individual bias for each tube is easily adjusted using the trim-pots and test points, conveniently located on the top of the amplifier. The Stingray’s power supply is extra-rugged and stiff, a Manley hallmark.

The proprietary audio connectors are gold-plated over brass with a Teflon dielectric, and an IEC receptacle located at the rear of the amp, allows the use of after-market power cords. Stingray’s sleek chassis is made from highly polished stainless steel, which will not rust or peel, like conventional chrome plate. Hand-turned, high-luster control knobs made at Manley’s in-house machine shop appoint the CNC machined faceplate, which is then plated with 24-karat gold. This results in a finish that is not only elegant, but durable as well. Stingray is quite the dapper gent.

To The Staging Lanes, Rev ‘er Up!

“Additionally, the lower registers were just as convincing exhibiting the weight and body commensurate with the instrument.”

My “fuel-delivery system” was the Parasound D/AC-2000 converter with Parasound’s C/BD-2000 transport, “gassing” the Stingray via Full Spectrum Audio Signature interconnects. WireWorld Equinox III speaker cables delivered the “horsepower” to my Eminent Technology LFT-8a speakers. The ETs were used with add-on Walsh-type super-tweeters, by George Mueller.

Later on in my evaluation, I used the Stingray with the same source components, to drive the electrostatic midrange/tweeter panels of my InnerSound Eros speakers. There the Stingray took the place of my current favorite amps, Monarchy SM-70s (used as monoblocks).

Starting with the lower octaves, this gutsy little amp delivered firm, extended bass, that sounded “real”. While many amplifiers deliver copious quantities of bass, few of them render sound like the actual bass instruments they’re trying to reproduce. The Stingray is one of the few amps I’ve heard that lets the listener believe that an electric bass, drum kit, or the lower registers of the piano could have been produced by the actual instruments.

Another facet of the Stingray’s bass presentation that impressed me, was its transition from the mid-bass to the upper bass–the area that affects male vocal reproduction. To check this out, I played a few tracks from The King Singer’s Good Vibrations (RCA/BMG 09026-60938-2). This album really blew me away, because the different sections of the chorus, bass, tenor, and alto sounded exceedingly natural and had the best reproduction of the hall ambience, that I can recall hearing. On their cover of Billy Joel’s “And So It Goes,” the interplay between the singers was riveting and the mid-bass, to upper bass, to lower midrange transition was virtually seamless. The bass and tenor vocalists had the perfect amount of “chestiness” to keep the presentation sounding natural and convincing. It wasn’t too dry, and it wasn’t too “DJ-esque”.

For a dose of kick drum and electric bass, I chose Erykah Badu’s “Rim Shot,” from Erykah Badu Live (Kedar UD-53109). The drum was very dynamic and very clean and the electric bass breathed a butt-gripping growl that smacked of authenticity.

I found the midrange reproduction to be as liquid and generally smooth, with a very good sense of nuance. Not only were vocals well served, but complex instruments like the piano were handled with particular aplomb. For example, on Gershwin’s Rhapsody In Blue (Delos DE 3216), the notes of the piano seemed to have just the correct proportions of attack, sustain and decay. With lesser electronics the piano can sound hard or glassy and the notes may not be reproduced with the proper amounts of attack and decay. With the Stingray, I found the character of the piano to be melodious and seductive, which is how the instrument sounds in a live venue. Yet the notes were clean and distinct and didn’t smear together.

Additionally, the lower registers were just as convincing exhibiting the weight and body commensurate with the instrument. In fact, at one point, my wife remarked about how true-to-life the piano sounded–and she was listening from the bedroom at the other end of our ranch–the next floor up…!

Strings, brass, and woodwinds proved themselves equally competent. Listening to “The Royal March,” from L’ Histoire du Soldat (Everest EVC 9049), the woodwinds acquitted themselves especially well, while the solo violin and the brass were rendered with their inherent sweetness and natural ease. This amp offers a good degree of immediacy and intimacy, never sounding sterile or mechanical.

The Stingray’s treble reproduction was also noteworthy. On tracks like US 3’s “Tukka Yoot’s Riddim,” (Blue Note CDP 0777 7 80883 2 5), the brushwork on the cymbals was detailed and extended, yet non-fatiguing. In my view, this is exactly how it should be on this recording. There was no hardness, edginess, or overbite. Also it seemed that high frequency percussion instruments such as maracas, shakers and even zydeco washboards, exuded a wealth of detail without stridency. Triangles and cymbal crashes on symphonic works were rendered very life-like and natural.

The soundstage was expansive and images were placed with a good degree of precision. I have heard some amps produce a touch more soundstage depth, but who can say whether this is accurate or an “effect” of some type? Also, I’ve heard some amplifiers provide a slightly more precise focus, with the trade-off being that they tend to sound slightly more etched.

Regarding the area of system dynamics, the macro-dynamic envelope of the feisty Stingray was very impressive (especially in view if the severe speaker load it was driving!). I didn’t discern any noticeable compression on sforzandos, and from the deft level of nuance it provided on the piano, on Rhapsody In Blue, I have to give it high marks for its expression of micro-dynamics too.

However, the above paragraphs were written in the context of the amp’s sound with the ET speakers. When powering the electrostatic panels of my InnerSound Eros speakers, the Stingray didn’t fare quite as well. In truth, the sound through the Eros was a bit brighter, in the lower treble. Cymbals and other high frequency percussion instruments were a little splashier than with my reference amps.

As I recall, I got similar results (in the treble) using a Music Reference RM-10 amplifier a while back; but the RM-10 was not as powerful, nor could it match the extension and punch of the Stingray in the bass. The bottom line is that the performance of all amplifiers is load dependent; and the character of a given amplifier will change a bit in accordance with the load that your speakers present (not to mention the unique sonic signature that one’s listening room will impart). For that reason I always suggest, whenever possible, that you audition any prospective amplifier in your own system before committing to the purchase.

Caveats?

I’ve already discussed the Stingray’s sonic presentation in detail, so I won’t repeat myself here. But there are a couple of ergonomic “barnacles” that I should mention. First, the on/off toggle is on the butt o’ the ‘ray and you have to feel for it from the front. Secondly, the dual-mono input selectors are located on the rear flanks (to shorten the signal path) and they are a bit inconvenient to reach as well. Third, although the binding posts appear to be of high quality I’m not in love with their design. I don’t like the way they hold banana plugs, and they are close enough together that spade lugs can short if not tightened securely. Lastly, the individual left and right inputs are far apart and at odd angles. This could make the use of some types of interconnects (stiff, inflexible audiophile-types) a bit problematic, especially if you will be installing the amp in an enclosed, or hard to reach location.

Conclusion

This is a great little amp. It’s a manly beast, spirited and lively, yet gentle as the recording dictates. A lot of thought went into its development and this shows through in its gorgeous eye-catching styling, and in its sonic presentation.

If you own inefficient speakers and like to blast them without caution in a high-volume acoustic venue, then you will need to buy a more powerful amplifier. Otherwise, this is a fine amplifier that provides a generous blend musicality and resolution. With it, you may find yourself forgetting about the hardware and simply focusing your attention on rediscovering your collection of recordings.

Plus, the Stingray really looks MARVELOUS! And if it ever stops working somewhere way down the line, you can always mount it on your wall like a big-game trophy. Then you can tell your grand kids impassioned stories about the “Big-One” that got away–minus the usual regrets … Highly Recommended!

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There’s an aesthetic dimension to the Manley Laboratories Stingray that transcends high-end audio and borders on modern sculpture—not unlike the E.A.R. V20, which I auditioned in the October issue. Still, the Stingray is by no means an exercise in gimmickry. Form has clearly followed function at every step in the design process, the ultimate goal of which was to fashion a vacuum-tube integrated amplifier with real-world power that defined the outer limits of high-end performance in a functional, affordable, bare-bones package…with a touch of style.

Still, while the Stingray’s aural charms ultimately proved quite engaging, I was initially captivated by its radical styling. To see the Stingray aglow in a darkened listening room is an oddly evocative experience—as if the Muppets, hired by Bayreuth to stage a Wagner opera, had decided to use a chorus of vacuum tubes in place of the usual sopranos, altos, tenors, and basses. And if the E.A.R. V20 reflected its maker’s fascination with high-performance European sports cars, the Stingray is like a visitor from some distant galaxy as seen through the retro-futuristic strip-mall prism of 1950s SoCal pop culture. Like, radical, man.

In fact, when EveAnna Manley sketched her hexagonal work in progress—on a bar napkin during a pause for the cause at HI-FI ’98 in Los Angeles—for erstwhile Stereophile Pooh-Bah J. Gordon Holt, that venerable sage remarked dryly, between sips of his even drier martini, “It looks like a stingray.”

Of such moments are legends born. In honor of JGH, this souped-up, highly evolved descendant of the venerable Manley 50W monoblocks was dubbed the Stingray. The fish is illuminated on the 24K-gold front panel in a manner befitting the trailer for a William Castle/Vincent Price mondo sci-fi epic. (“No audiophiles will be seated during the final 15 minutes of this demo! Please don’t reveal the surprise ending to your friends!”)

It takes a village to nurture an amp
My wife, quite taken by the unconventional appearance of this curious new denizen of our audio menagerie, was pleased to learn that its overall design was the vision of a female audiophile. “It looks like a little village,” she concluded. But while the essential vision was indeed that of Manley Labs’ guiding light, it took a village of dedicated audiophiles, or at least Manley Labs’ dedicated team, to raise such a child.

It’s tempting to characterize the Stingray as an extension of EveAnna Manley’s own personality: bright, brassy, forward, good-natured, in your face—in a word, dude, rock’n’roll.

“Well, I can’t admit to consciously trying to inflict my personality on the sound of this gear, but I will admit to listening to a lot of rock’n’roll music,” Manley laughs. “Music has such a powerful associative property for me—it’s emotional. True enough, I played saxes and clarinets and a little trumpet in high school and college bands and orchestras, and even got a degree in Music, so yeah, I know my music theory and I do know what real instruments sound like.

“Now, because we build all of this pro recording equipment, I find myself in a lot of recording studios and mastering rooms, and, this being the music industry, most of it is pop or rock’n’roll music, so that becomes my reference. But you know what? A lot of the evaluative listening process is a relative thing, whether you’re involved with acoustic purist music or multitrack recordings—once you know anything rather well, relative listening comes into play. Can you hear the detail of the beads on the shaker, the tone of the guitar, the decay of that hall, the solidity of the bass attack?

“Hey, Robert Plant’s voice was once an acoustic instrument, just the same as that trombone was. They were both floating through the air until some microphone picked up the sound to convert that air movement into some little volts to be made into some bigger volts to get moved through a bunch of gear onto a storage medium, which we can later buy and do the reverse to.”

While the Manley Stingray has only one power transformer, it is essentially a fixed-bias, dual-monoblock configuration on a single stainless-steel chassis. It has sets of separate left and right line inputs (gold-plated brass with Teflon dielectric) positioned to either side of the chassis and adjacent to their own output transformers, a four-position silver-contact input selector switch, and screw-down-style binding posts.

Ideally suited to accept spades or bare wire, these old-fashioned-looking posts are positioned close enough to the back of the output transformers that using a pair of pliers is a tight squeeze. Nor was I able to piggyback a second set of speaker cables with WBT expanding bananas for a biwire setup, as I had with the more versatile vertical binding posts of the Mesa Audio Tigris and the E.A.R. V20. My handy-dandy Dynaclear Postman (with its ½” and 7/16″ slots) didn’t work here, making it a bit clumsy to change cables. If I’d had an adjustable wrench or a 3/8″ nut driver, I’d have been cool.

The Stingray’s hexagonal shape—essentially a square with the front and back corners cut off—evolved from Manley’s desire to keep signal paths and connections as short and direct as possible so as to employ a passive preamp instead of a gain-stage device. Which is why a pair of bullet-shaped aluminum pillars serve to conceal and gussy up the left and right corners, and double as the conical feet on which the amplifier rests.

And so, in detail after detail of the Stingray, form follows function. Thus the decision to employ, for exceptional transparency, a passive preamp and high-quality passive Noble volume and balance controls.

“The main functions of preamps these days are switching and volume,” Manley explains. “When you have to drive only a few inches of wire, as in the Stingray, and all your sources are a couple of volts output, as they mostly all are these days, a passive preamp works great. Some guys, thinking less is more, get in trouble with passive preamps trying to use a 50k ohm potentiometer to drive 12′ of whatever capacitance in the cable. Whoops? Where did the balls and high frequencies go? Gotta get down to some low impedance to drive cable properly without loss.

“Another way that the form followed function was having the power switch next to the IEC connector. If I had run the power switch up at the front panel, then the mains would have had to flow right under the input circuitry. By keeping the power switch at the back, where it’s easily accessible, wiring—and thus labor—are greatly simplified, and all the AC is kept furthest away from the sensitive input stages.”

The most remarkable thing about the Stingray is the amount of gain and dynamic range Manley and her design team managed to elicit from four little EL84 output tubes per channel—not exactly a tube that springs to mind when envisioning a 50W amp of low global feedback (only 4dB) operating in ultralinear mode. All sparkly, quick, and open, the EL84 has never been synonymous with prodigious bass, but the Manley team reasoned that perhaps this was not the tube’s fault. Because Manley Labs winds its own transformers, “Hutch” Hutchison was able to define a new series of parameters, Michael Hunter could wind some prototypes, and, in short order, Paul Fargo would have one hooked up to an amplifier on the test bench for measurements and A/B listening tests with the old designs.

As Manley describes it, ” ‘Sorry, boys,’ I’d tell them. ‘Your numbers are way better with the new designs, but we’re still not there sonically. Try again.’ So what actually ended up happening was a balance of numbers and ears. The bass sound I was looking for came from the right amount of inductance combined with a slight introduction of saturation. ‘Oh, the horror!’ you say. Nope, numbers ain’t everything…as you may have heard. The other place we found we were losing a little bass was in the old input stage we’d been using for the past 15 years. So Paul Fargo developed a new input design that really did the trick. And it suited us well, with the Stingray’s passive volume and balance control, to score a little extra gain there anyway. And Mr. 12AT7 takes care of that job.”

Bright lights, fast city
In high-end audio, the name of the game is system synergy. As taken as I was with the Stingray’s sound, I set out to audition it in a variety of applications, with different combinations of tweaks and gear. I tried both short-wall, nearfield settings (with a variety of stand-mounted speakers)—in which, I anticipated, some Stereophile readers might use the amp—and full-range floorstanders in my customary long-wall space. (See “Associated Equipment.”) I also did a fair amount of comparative listening with a pair of similarly priced integrated amps that were visiting for the summer: the 6V6/EL84-equipped Mesa Tigris and the EL34-configured Conrad-Johnson CAV-50.

During this time I also experimented with speaker cables with each integrated-amp/speaker combo, alternating between the more passive, linear, midrange-oriented JPS Superconductor Singles and the remarkably rich, triodelike contours of the new, more subjectively voiced Monster Cable Sigma Retros. And, most significantly, I got to upgrade the performance of all my analog and digital components with the new Synergistic Research Designer’s Reference² Master Couplers. These are, for my critical listening purposes and sheer aural exhilaration, an absolute reference point of sonic integrity. The manner in which they optimize system performance/synergy and reveal all sorts of anomalies and sonic warts at every level is incredibly revealing, and the degree of bass extension, midrange resolution, and top-end air they let shine through is a revelation. They make good components sound great, and great components sound positively surreal. All of a sudden, I was in no hurry to “upgrade” any of my core components. Damn, high-end audio is fun!

Cassandra Wilson’s beautifully recorded Traveling Miles (Blue Note 8 54123 2) proved ideal in illustrating the Stingray’s essential musical character, harmonic correctness, and ease of resolution with acoustic and electric sources, fast transients, and the human voice. My initial impressions of the Stingray were of its incredible speed and tonal brilliance. On “Time After Time,” the localization, separation, and detail of specific images, such as the acoustic and electric strings in the left and right channels and the enormous acoustic bass, were clear and lucid; each instrument was distinctly delineated in its own acoustic space, yet elegantly blended with the rest.

Wilson’s voice was beautifully centered and richly detailed, from the chesty mezzo character of her tone to the breathy aura of her phrasing and articulation. Nor—unlike many of the amplifiers I’ve auditioned of late—was there anything laid-back or rolled-off about the highs. The upper harmonics of Regina Carter’s fiddle had wonderful sparkle and life on “Seven Steps to Heaven.” Tiny percussive details were clearly rendered, the piano and vibraphone were never muddled in midrange murk, the soundstaging was deep and open and holographic, and there was plenty of attack and forward thrust to the bass—super rhythm and pacing, if not the last word in heft.

Likewise on the hypnotic gamelan airs of “Metalanguage,” from Alternesia (M•A Recordings/Series Momentum M3), by my worthy colleague and fellow percussionist, Jon Iverson. This is a fantastic full-range recording with exceptional air, soundstage depth, and low-end slam, thanks to Jon’s use of a venerable 2″, 16-track MCI. The Stingray collated the swelter of metallic, wooden, and skin voices like a spinster librarian, seemingly sorting out and cross-referencing all the tonal focal points by height and age, in alphabetical order.

And on “Asking For It,” from Hole’s Live Through This (DGC DGCD-24631), the Stingray handled all the ambient effects and acoustic cues with classical ease and aplomb, then easily shifted into overdrive to track Courtney Love’s gargling-with-grenades voice and the band’s crunchy garage-band roar with the kind of snap, crackle, pop, and elemental swell that more polite audio designs never approach.

In my secret identity of Clip Stern, high-end audio’s Vlad the Impaler, I’m always driving amps to destruction. So it was with the Stingray and its mechanically detented volume control (not to be confused with much more expensive graduated switched resistors, to which it bears a superficial resemblance). Depending on the source, I found that, as I increased the volume, the Stingray got a little louder, then a little more loud, then a bit louder still—until suddenly there was an abrupt jump to A LOT LOUDER as the amplifier delivered its singing telegram: “Hey, schmuck, you have reached the outer edges of this system’s performance limits. Back off!” I found myself wishing I could dial up a setting somewhere between 7 and 8.

But you know what? The electrical contact of the Stingray’s volume control is actually continuous, like a normal pot; it is ball bearings that give it the feel of those little mechanical clicks. By backing up so the ball bearing didn’t quite rock over to the next click, I did find an in-between step that seemed to represent the optimum median gain before shifting over into Glare Central.

Comparisons
No integrated amplifier in this price range is going to have everything, and in one-on-one auditions with the Mesa Audio Tigris and the Conrad-Johnson CAV-50 the Stingray more than held its own—and was, in some ways, the most musically satisfying. Still, each amp had its own areas of emphasis and strength. A matter of personal taste. The best way I can characterize the differences is that the Stingray sounds as if it was voiced from the top down, the Tigris from the bottom up, and the CAV-50 from the midrange out.

I found the CAV-50 to be euphonic and fairly bloomy: rolled-off on the top, laid-back on the bottom. I was pleased to discover how sensual and harmonically correct it rendered vocals, and had a lot of fun blowing doors off hinges with large-gestured symphonic recordings, without the sound getting grainy or glaring—a very lush, romantic presentation. However, it didn’t quite deliver the elemental bite and bark I want from rock or the rhythm and pacing I prefer with acoustic jazz, tending to favor the warm afterglow of upright bass rather than tracking the leading edge of attack transients. Of course, the CAV-50 uses an integral power cord, so I wasn’t able to confer on it the sonic benefits of a state-of-the-art power cord like the Designer’s Reference² Master Coupler. Hardly seems fair, does it? Still, employing the JPS Superconductor Single speaker cables—a fairly linear design with a detailed, articulate midrange and a bit of extra juice in the presence region—really helped localize the bass and gave the CAV-50 more air and presence on top. System synergy is everything.

The Mesa Tigris is, in some ways, the most versatile of these three amps, what with its dedicated headphone amplifier and the multiple pentode/triode/negative-feedback combinations of its Tandem State Imaging. It has terrific slam and bass resolution, a sweet, smooth top end, a warm, musical midrange, and fine soundstaging. I love listening to rock and driving acoustic jazz on it. But as I intimated in writing of its multiple personalities in my original review, it’s less powerful, and more colored or subjective in its presentation—which means it doesn’t have the upper-midrange articulation and see-through clarity that make the Stingray more satisfying for a greater variety of acoustic sources and rock. For the Tigris to match the gain, headroom, and soundstaging depth of the 50W, ultralinear Stingray would necessitate adding progressive increments of negative feedback, which would make it much more linear and significantly increase the dynamic range, but with a commensurate loss of transparency.

The Stingray had little in the way of upper-bass bloom or plumpness. Its bass was still much faster and more forward than the CAV-50’s, if not quite as fat and immediate as the Tigris’s. Still, the speed and accuracy with which it portrayed bass were quite musical, the midrange was exceptionally clear, open, and articulate, the presence region had real bite, and the high end was detailed and brassy. I would not recommend using the Stingray with exceptionally bright or analytical speakers, as the sonic aftermath could be likened to the penumbra’s effect on the eyes during a solar eclipse.

Conclusions
The Manley Laboratories Stingray is a carefully thought-out, lovingly designed integrated amp with a big, open soundstage, a shimmering, crystalline top end, a clear, richly detailed midrange, and a lean, focused, articulate bass response with such superb speed and pacing that it more than compensates for its lack of extreme low-end heft.

Which is not to say that the Stingray doesn’t have beaucoup bass. With small, warm, efficient bookshelf speakers, the Stingray’s sound was rich, vibrant, and alive, with plenty of pep, detail, character, and punch. It was shocking how rich and musical the Stingray sounded with the humble little PSB Alpha minimonitors and the warm, sweet Soliloquy 5s.

Which is not to say that it lacked the guts to drive big full-range speakers…provided they have the requisite sensitivity. At HI-FI ’99 in Chicago, I heard the Stingray drive the big Tannoy Churchills to purr-fection, while with my full-range Celestion A3s—in tandem with the warm, airy, triodelike midrange character and plump, autumnal upper-bass emphasis of the Monster Cable Sigma Retros—I was able to get as vivid, balanced, and involving a sound in my listening room as I’ve ever experienced.

All in all, the Stingray is cool, sexy, and musical. But mostly, it’s fun.