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Positive Feedback ISSUE
e.One Ref 1000 amplifiers - Confession is good for the soul ...Not!
as reviewed by Chip Stern
You know, sometimes the creative process involved in fashioning one of these audio reviews is fairly complex, while at other times, the thing speaks for itself...or perhaps we should say, the object of our affection allows the music to speak to the listener in such a direct emotional manner that...well, what more is there to say?
However, if your birth certificate says Chip Stern, it seems as though there's always more to say. I tend to get obsessive about the review process, to take out the prayer rug until I have exhausted every possibility for analysis as the seasons change, the leaves fall from the trees and a succession of readers e-mail me wondering when they might expect to peruse my thoughts (the better to validate their own intentions).
I put myself through these gyrations in part because I am slightly daft but mostly from sheer force of habit. Over time I've evolved a specific template: a scene-setting overture; some talking points for the designer; a detailed explication of features, performance parameters and the listening process, replete with numerous listening examples; and an epilogue featuring my final conclusions in which inevitably I feel compelled to act as both advocate and prosecuting attorney—to state the case both for enthusiasts and those Doubting Thomas-types who won't necessarily gravitate towards a particular piece of gear, irrespective of its quality, for their own purely subjective reasons.
All of which stems from the recognition of how privileged I am to linger with way cool gear for such extended conjugal visits. As the aesthetic proxy for those readers whose access to audition time is far more limited, I've always tended to go over the top, to really pile it on, in the hope that I'm able to depict the gear's sonic signature as vividly as possible.
However, there are times when I'm unsure how all this obsessing really helps the average reader. In some recent pieces, where my enthusiasm for certain loudspeakers seemingly knew no bounds (the Dynaudio Confidence C1 and the Acoustic Zen Adagio), the reviews went on (and on) for thousands upon thousands of words—until many readers' eyes began to glaze over—yet I'd still get e-mails from people wondering what I "really thought."
Really thought? "Well, if I read between the lines correctly..." Read between the lines? My friend, that Confidence C1 review is in the neighborhood of ten thousand words...there wasn't enough space between the lines for oxygen let alone for some trail of high end audio bread crumbs—I DON'T WRITE IN CODE.
But I do go on. Perhaps I'm simply in love with the sound of my own voice; maybe after a while the writing becomes a thing onto itself, and I get caught up in the perfume of my own music—after all, not for nothing have I been hailed as the Maharaja of Metaphor, the Sultan of Simile, verily, the Avatar of Aural Awareness.
Aw, shucks ...487 words (marked down from 575) just clearing my throat—somebody stop me!
Not exactly off to a blazing start are we? Let's see if I can't tighten things up a bit as we go along ...parse, Chip, parse now boy.
Big Things, Small Packages
Having thus expended all that verbal ordinance in lip service to brevity, allow me to suggest that those of you in the market for an amp that embodies both sheer power and supple aural refinements, surely owe it to yourselves to audition a pair of Bel Canto e.One REF1000 monoblocks at your earliest possible opportunity—they offer a remarkably musical set of performance parameters in a surprisingly practical format.
I was initially drawn to the Bel Canto REF1000 monoblocks through a pair of aural intermediaries whose ears and musical values I particularly respect: fellow Positive Feedback contributor John Potis and Joseph Audio honcho Jeff Joseph.
I hold John Potis in very high regard, and feel he is among the very best audio writers on the scene. John has always had a passion for the elegant sonic signature of low-powered tube amps (such as the Art Audio Carissa, the Canary CA 330 and the Opera Audio Cyber 211), whereas I've always been drawn to the dynamic possibilities of power, and so when he began speaking with something approaching real reverence for the REF1000's I took heed. He spoke enthusiastically of their seemingly limitless reserves of power, their tube-like warmth and most significantly what he described as a real sense of "presence" in their portrayal not only of small musical details, but the totality of a musical presentation. I first heard them down at his crib in Maryland, but my impressions were of a more general nature—we listened to many interesting combinations of gear that weekend, along with a memorable visit to the Conrad Johnson facility in Fairfax, Virginia, but John's enthusiasm for the REF1000 stayed with me, as did some back stories in which he related how Bel Canto 's John Stronczer had arrived at his cutting edge epiphany about modern solid state technology from a sophisticated grounding in tube design. Hmmmmm...
But what really sealed the deal for this Pilgrim was when the noted audiophile and photographer Michael Polizzi and I made a bee-line for Jeff Joseph's Hyatt suite on opening morning of the last Stereophile home entertainment show in NYC. Michael was keen to hear the RM33LE loudspeakers Jeff was showcasing, a design upon which I had logged considerable flight time, having reviewed them with great enthusiasm in their two earlier iterations for Stereophile (closing with a suggestion that Jeff deploy the same exalted SEAS tweeter in the RM33si as he employed in his top-of-the-line Pearls). I never did hear the RM33LE with that special tweeter, so I was quite keen to audition them as well.
Now in my experience, while Jeff's loudspeakers present a fairly benign load to an amplifier (I am presently driving a pair of RM25siMKII loudspeakers to perfection in my wife's piano studio with a 28 watt Mesa Tigris tube integrated amplifier), the RM33si benefited from having some serious current behind them. Still, as much experience as I had listening to the RM33si in my own crib, and as fantastic as the detailing and soundstaging always were, I'd never heard them dance with anything approaching the dynamic snap, crackle and pop they were strutting that spring morning...
In tandem with sundry Bel Canto DACs, transports and other goodies, the REF1000 monoblocks at the Hyatt suite drove the RM33LE effortlessly to live music concert levels, enhancing their already exceptional soundstaging and low level resolution, accentuating the loudspeaker's inherent clarity and transparency, adding layers of depth and detail to the Josephs while maintaining a firm control of the bass drivers that helped fully realize their low frequency potential, not as boom or girth but as depth of field, as speed and transient impact—a palpable physical intimacy that enhanced the speakers' ability to really boogie in a natural, unforced manner, neither particularly bright nor etched nor analytical, but rather, warmly resolved with the requisite fully fleshed out midrange to die for. Nor was the sound at all bright or etched in a clichéd solid state manner.
Leave it to Jeff Joseph to cut to the chase: "They weigh like 13 pounds a piece, take up no space whatsoever, sound great and are very affordable—what's not to like?"
What indeed? The REF1000 deliver a no-nonsense 500 watts per channel into 8 ohms and 1000 watts per side into 4 ohms (purportedly maintaining their stability in the presence of 2 ohm loads), more than enough power to fully energize a good-sized room with even the most power-hungry loudspeakers, and all for $3995 a pair?
Where do I sign?
The REF1000 monoblocks are analog switching amplifiers, employing an ICEpower module based on technology first developed by Dr. Karsten Nielsen and Bang & Olufsen, which as I understand it raises the efficiency of the audio power conversion chain (which we may define as the path from where you initially plug in to the electrical grid to final sonic output), while eliminating the need for bulky heat sinks and potentially noisy transformers. So impressed by this technology was Bel Canto honcho John Stronczer, a much-respected audio designer with a devout vacuum tube pedigree, that he changed horses in midstream ...no, make that changed horses at full gallop, committing his considerable engineering acumen to work in perfecting the musical potential and audio applications of this technology.
In the case of the REF1000, the resulting product is a true balanced design that features a fully regulated power supply that draws negligible power at idle, running as cool as a Miles Davis trumpet solo in a remarkably small footprint package (8.5" W x 3.0" H x 12.0" D), with desirably short signal paths, and a minimum of output devices, a "balanced input [that] insures that the large output/input power ratio does not corrupt the input signal fidelity."
The resulting sound evinces exceptional clarity and low distortion performance, with a vast dynamic range specked out at 120dB, low output stage impedance, and an exceptionally high damping factor.
In browsing through a Bel Canto white paper on the relative merits of the REF1000's technological pedigree, Stronczer draws comparisons with single-ended class A, push-pull class A and push-pull class AB, ruminating on their relative merits and tradeoffs in terms of bias, thermal stability, linearity and efficiency. Likewise, "tube output stages typically require a coupling transformer to match the low impedance of a loudspeaker to the high impedance of a tube circuit."
By contrast, the REF1000's ICEpower analog switching output stage "...uses 2 Nchannel MOSFET switches per phase (4 devices in a balanced/bridged output). These power devices are switched between the power supply rails. They turn on and off within 30 billions of a second and provide an on resistance path to the supply of less than 30 thousands of an ohm. These switches switch alternately between the supplies at a rate that averages 500 thousand cycles per second (500kHz). These 4 power devices can deliver many hundreds of watts of power to the loudspeaker...when no audio signal is present the ratio between the time at the positive supply and the negative is balanced to provide no audio frequency output. The switching stage is isolated from the loudspeaker by a single Inductor/Capacitor (LC) filter that removes energy above 80kHz ...the audio signal controls the output stage by changing the timing of the switching edges. The critical timing information is controlled by the feedback loop processing and the effective switching frequency is changed over a 200kHz to 1500kHz range."
The white paper goes on to claim that the REF1000's "...output stage does not suffer from the distortion mechanisms of analog output stages; crossover distortion, thermal bias wander and multiple device variations...important measures of amplifier performance such as Total Harmonic Distortion, Noise and Transient Inter Modulation Distortion (TIM) levels are extremely low across the audio band at all power levels."
Before my eyes began to glaze over, I took note of how Stronczer characterized the differences between ICEpower architecture and that of Class D switching amps. The latter employ "...a Pulse Width Modulation algorithm to control the output stage switches. This is generated with relatively simple analog processing and a crude digital to analog conversion based on a fixed frequency triangle wave. Traditional analog feedback is used to reduce the distortion produced by the analog processing to acceptable levels. This approach has numerous drawbacks and can produce high levels of THD and IMD. The fixed frequency of operation also requires extreme care in designing the output filter to insure that switching noise is low enough. Changes in frequency response based on the loudspeaker load and phase deviation at high frequencies result. The e.One ICEpower architecture has linear phase response, low levels of TIM distortion and THD performance consisting of low levels of low-order harmonics in a natural descending progression, much like many tube amplifiers and better solid state linear amplifiers."
In conclusion Stronczer also points to how the soft clipping characteristics of the REF1000 amplifier mimics the overload characteristics of tubes, preventing the harshness that occurs with many solid state amplifiers. "This soft clipping does not cause any compromise in the performance at levels below clipping."
More Power, Scotty
That last point kind of set off bells in the back of my brain, recalling when I first got these amplifiers in-house, during the latter part of the winter as I recall.
There was a pretty long stretch where I apparently had whatever bug was going around, and for a considerable period of time, my listening was likely quite compromised. I say likely, because I was so zapped, I didn't realize the full implications at first...I just kind of got used to an extended period of time with incredible head congestion where one ear was pretty much shut down, and I didn't truly realize how messed up the other ear was.
That is until I found myself seemingly driving both the Bel Cantos and the Rogue M150s well beyond their limits. I say seemingly because I was kind of slow on the uptake, and at the point where everything I played seemed to be going crunch, it slowly dawned on me that I was in no position to do any critical listening. This seemed to last for the better part of two months before with the onset of spring, my head finally cleared up enough that I could clearly hear with both ears and began to trust my senses again.
But it was during that time that I became aware of the limits of both sets of amplifiers, and I discovered the one real kink in the REF1000's armor, which was how it behaved when driven into clipping. It's worth pointing out that it took a moron like myself, his head full of snot, driving the living piss out of his whole system to make up for what he wasn't hearing, to even begin to realize that neither set of amps lacked power or resolution but that, again, my hearing was utterly compromised. From the sketchy notes I took during that period, I noted that the Rogue kind of got this glare on when driven well into clipping, and that the Bel Cantos evinced a kind of clicking, an almost percussive kind of noise. Some listeners, more experienced than I, spoke of a variety of digital noise artifacts that often pervade the world of switching amps. How this applies to the REF1000 monoblocks, which are analog switching amps, as opposed to Class D switching amps, is beyond me. But in my lunacy, I did make the REF1000 amps clip, and it was a curious experience.
I need to point out that for all the reserves of power both amps possess, any amp can be significantly overdriven, generally because you have too much room to fill, too demanding a speaker load (or too much phlegm between your ears). Having said all that, the Bel Canto REF1000s proved to be remarkably musical performers on every level, and given the finicky nature of audiophiles—well, given the finicky nature of this audiophile—I remain impressed by how easy they've proven to live with and how little I have to quibble about at the tail end of the review process.
It's also worth reiterating that once I got my sea legs back under me, and was thoroughly douched out between the ears, I never experienced anything vaguely approaching clipping again, because I rarely had to raise the volume knob on the VTL 5.5 preamp much past 9-10:00 o'clock the most on your typical commercial audio releases, and often below that on hotter masters.
Bel Canto suggest that listeners looking to engage in serious auditioning allow the REF1000s to run continuously for at least 40 hours with some sort of input signal and thereafter should be allowed to remain on all the time—at which point they begin to stabilize and attain their true voice. During the final stages of listening while composing this review, I had them on for a period of several weeks and I certainly found this to be the case. Everything became smoother and more relaxed, there was a greater sense of ease to the dynamic swings, transients seemed more nuanced and realistic, all of the little details became more vivid and soundstaging took on a more profoundly spacious, airy, expansive nature.
John Stronczer also suggested that during my audition process, I try listening to the REF1000s with my Equi=Tech 2Q (connected to my main 20 amp dedicated line with a JPS Labs Aluminata AC Cord) removed from the circuit. Many people have suggested to me that because of the transformer-less nature of switching amps, a balanced power isolation transformer like the Equi=Tech 2Q would have negligible effect ...and might even take the sound south in some unforeseen and unpleasant manner. I cannot speak scientifically to these assertions; all I know is that when I plugged the REF1000s directly into my 20 amp line (with two additional JPS Labs Aluminata AC cords connected to a long run of JPS Kaptovator AC cable configured as an Outlet center and extending well into my listening room from 20-25 feet downstream in my adjoining room where the dedicated 20 amp outlets are situated), I went the A/B route for about 10 minutes, and finally decided that while the Bel Canto's sounded good without, there was simply more there THERE with the 2Q/Aluminata rig feeding both power amps current—more resolution and better dynamics; more profoundly engaging bass extension, quickness and transient impact; deeper soundstaging, superior center-fill and stereo imaging focus—and so I kept my reference system signal chain precisely as it has been for some time now. Were the differences I noted either with-or-without drop dead dramatic? No, but then I didn't ponder the issue long enough to make such a bald assertion. The differences were certainly discernible to me, like when you go from a $4000 CD player to a $10,000 source component—surely the 2Q/Aluminata combo didn't make things sound less engaging. Having so quickly validated my original preferences, we moved on.
While composing this piece I took note of some nimrod's suggestion in print that the Dynaudio Confidence C1 mini-monitors were so lacking in rock and roll impact and string quartet resolution that he wouldn't deign to let them linger in his system. A pretty superficial judgment, if you ask me. I was especially impressed by the degree of authority with which the REF1000 drove my reference loudspeakers, and I was particularly taken by the degree of control and authority they conferred to the music at lower volume levels. Things sounded solid and anchored and resolved and impact-ful.
In my experience of amplifiers, there inevitably seems to be a certain point you have to drive them at before they really begin to open up reach their true voice. With the REF1000 I found that the amp's reserves of power and top-to-bottom-linearity were such that they had a surprisingly "full" presence even when driven at more modest volume levels. And while this generation of Dynaudio loudspeakers is considerably more sensitive than earlier generations I have experienced, they nevertheless like their power, and I have been consistently blown away by their performance in systems employing such powerful, high quality amps as the tube Rogue M150 monoblocks and the Simaudio W-7M monoblocks.
Like the imposing Simaudio W-7M, the REF1000 are rated as 500 watts per side into 8 ohms and 1000 watts per side into 4 ohms (the rated impedance of the Confidence C1 being 4 ohms). I found that the REF1000 in no way, shape or form took a back seat to the Sim in terms of transient snap, bass control, dynamic headroom, detailing, soundstaging depth, clarity or midrange layering, and we're talking about a set of monoblocks almost comically smaller, lighter and cooler running—let alone selling for four times less! Gives one pause, yes it does. Not to in any way discount my enthusiasm for what I heard the Simaudio W-7M do in the Dynaudio suite at the same Hotel Hyatt show in which Brother Polizzi and I heard the Josephs and the Bel Cantos—they had one hell of a game of "hide the subwoofer" going in their suite, and no one could comprehend how those little-bitty C1's were putting out such clean, clear low frequency response with no sub and two drivers.
Well, duh...sure you could get more bass authority and a more fulsome depiction of the bottom octave (let alone more sheer bass energy) with full-range, floor-standing speakers, but in that modest room, when driven with sufficient power, the C1s boogied like there was no tomorrow. Polizzi has a pair of multi-driver Confidence C4 towers in his crib, driving them with a McCormack DNA-500, whose power is commensurate with that of the W-7M and the REF1000, but his room is like 16' x 27' (8 foot ceilings I think), so he has a longer, more deep-throated acoustic space to fill, and with a meticulous set-up, you can get a really beautiful balance in his room and not simply overdrive it with bass. In my room, the C4s would be little more than a tit on a whale, just too damn much speaker for the room, and the balance would be more skewed towards the bass (let alone what my poor neighbors would be experiencing...like a hippo coming off of an Alpine ski jump...and right through the ceiling).
Part of the equation in matching a system to your room (and mine is 14" x 20" with ten foot ceilings) is your expectation of how the speakers will couple with the room and energize it. The C1 blast out plenty of level at 31Hz on the Stereophile test CD, and that represents the bottom octave of the piano (low A is like 27Hz). Of course it takes some serious juice to energize any room with a single bass-midrange driver, and this is where amps like the REF1000 give you such an incredible foundation of sound from top to bottom, by riding that Dynaudio bass driver like a rodeo star, never letting that bull buck and toss the rider, nor running out of power and shortchanging the midrange or critical high frequencies and inflicting all manner of distortions and colorations on the poor listener. And I played plenty of electric rock and funk from the Pretenders (The Singles), Emmy Lou Harris (Red Dirt Girl) and The Very Best of Chic to reassure myself that the REF1000 were projecting the dynamic headroom to realistically portray the transient power of the bass and the drums, but to do so with plenty of clarity and refinement in reserve—the better to depict the concomitant web of complex textures in the mix, as well as the pristine textures and spatial relationships of an acoustic recital of Haydn's String Quartet in D Major from the group Engegårdkvartetten on String Quartets (one of a wonderful series of impeccable DSD/hybrid/SACD acoustic productions from producer-recording engineer Morten Lindberg for his Norwegian 2L label), while splitting the difference on front row, high rez/hot mastered, loud/soft, acoustic/electric jazz soundscapes by the likes of such high end audio all-stars as Bill Frisell/Ron Carter/Paul Motian, John Scofield (with Steve Swallow and Bill Stewart on This Meets That) and an advance CD of vocalist-pianist Patricia Barber's latest aural sonnets for the Blue Note label, The Cole Porter Mix.
Now that it's time to pack ‘em up, how would I characterize the sound of the REF1000s? Were they indeed tube-like? I'm not so sure about that, but they were surely warm and mellifluous, which translated into a very mellow yet detailed top end and a warm, open midrange. The tonal balance of the amps was fairly neutral, linear and balanced, with a more softly, firmly delineated depiction of high frequencies. I never really felt myself wanting for treble detail, but depending on what speakers this amp is going to be matched with, I suppose it might seem a tad opaque to the beholder. So while the REF1000 were an excellent match for the floor-standing Joseph Audio RM25siMK2 and the exceptionally detailed, brilliantly resolved C1, when paired with the richer sounding Acoustic Zen Adagios, with their rounder bottom end and subtle ribbon tweeter, the Bel Cantos seemed too much of a good thing to these ears, and I found the tube Rogue M150 monoblocks conferred more midrange presence and sunshine, more high frequency sparkle and shimmer, a bit more transparency...in the latter case, a good match versus a great match—game to tube amp.
But man, listen to how the REF1000 helped the C1 to deliver the subterranean low bass pedal tones on "Bang the Drum Slowly" while illuminating a multi-tiered canvas of tiny lights in the lateral domain, and centering Harris's processed vocals like some luminous balloon in the half-light of dusk. Even more revealing was how the Bel Canto's back lit the exhalations of Barber's husky, gossamer solo voice on the opening stanzas of "Miss Otis Regrets" with such stark, close-miked intimacy and surreal clarity.
I'm Built For Comfort ...I Ain't Built For Speed
At this point in the review, I would normally take a deep breath and micro-analyze every little nuance of several musical selections, but I suspect I've pretty much zeroed in on the qualities I like about the REF1000, so in the interests of letting my dear readers get on with their lives, and allowing the REF1000s to say goodbye to their sleep-away camp companions till some other spring, let me cut to the chase.
I think it's pretty clear that if like me you have some two-way monitor speakers, in a mid-sized space, and you want something both dynamic and expansive, colorful yet colorless, snappy yet sweet—where your amp positively, absolutely has to possess enormous reserves of power to make such a small speaker sit up and wag its tail like a big dog (yes your are), then for $3995, the Bel Canto REF1000 are a lot of amp for the money. They don't draw undue attention to themselves, are unobtrusively efficient and possess exceptional drive, delivering oodles of power with no discernible distortion or untoward colorations. You have to practically be demented (as I was) to drive these motherfuckers into clipping, yet you can generally drive your speakers as satisfyingly loud as you like, and still retain much of that snap, crackle, pop and tonal balance at lower volume levels.
Compared to my Rogue M150s? Well, these are both very good amps with contrasting perspectives— two different ways of skinning a cat from two different amps with a lot of drive. Equivocating, Chip? Okay, okay, let's see. I find the Rogues to be visceral and expansive; the Bel Cantos are warmer and smoother. Both amps deliver a lot of what John Potis characterizes as presence, but I'd say the Rogues do it in a slightly more aggressive manner, while the Bel Cantos are more laid back. The Rogues in an ironic kind of aural twist, have this radiantly textured midrange and a livelier, brighter top end (which I guess one might more readily equate with solid state) for a more shimmering sunlit canvas, like a Van Gogh flower setting or field of grain. Meanwhile, in another bit of role reversal, the Bel Canto's smooth, rounded top end is decidedly tube-like; from top-to-bottom the Bel Canto is more even and less peaky (not that the Rogue is some sort of tonal roller coaster), projecting more of a sepia/film noire glow, somewhere between Raymond Chandler and Ansel Adams.
The Bel Canto's control of bass is exceptional but the Rogue's might even be a little more authoritative: I was particularly impressed with how well both amps decoded Steve Swallow's woody bass guitar—heavy on low end pedal tones, light on leading edge transients, picked rather than plucked—throughout Scofield's This And That. Perhaps we could characterize the Rogue's depiction of bass as bigger, snappier and more exciting, the Bel Canto's as more centered. And while the Rogue offers exceptionally linear performance from a tube amp, the Bel Canto is more even from top to bottom. And while the Rogue is hardly a wildly colored my-fi tube component (in fact, it represents one of the least subjectively colored tube amps I've experienced) it nevertheless projects more tints and shading on the sonic canvas (which I am not perturbed about in the least), while the Bel Canto projects a very muscular brand of cool, all shadow and light.
TANGENT ALERT: In fact (and thanks to Positive Feedback reader Jon "More Chips & Beer" Morstad for his kind thoughts and proto-plebian nudge), at the very end of the listening process for this review, I found that an interesting byproduct of the Bel Canto's muscular cool was how well it mated with my Manley Massive Passive Stereo Tube Parametric EQ when I introduced it into the circuit.
[Cue anal retentive audiophiles] Heretic, heretic! Tone controls are so déclassé. Well, with all due respect, bite me. Where is it written ...oh, yes, it's written right here, in the Audiophiles Ten Commandments of Received Wisdom and Eternal Douchebaggery ...thou shalt not sully thy sound, oh thank you your holiness—what was I thinking? Never mind the influence of room anomalies or the wildly divergent state of different sonic sources; so its okay to tweak things employing cables very much like tone controls, or by using power conditioning and acoustic panels, let alone mating warm speakers with analytical source components...etcetera, etcetera, etcetera. But no tone controls or wire hangers ...ever!
I understand that some cheesy tone controls, like one size fit all op-amps, introduce colorations and distortions into the signal chain; however over the years I've enjoyed excellent gear from companies as varied as Luxman and Linn that featured subtle, musical, useful tone controls. Hell, I remember speaking with esteemed speaker designer Richard Vandersteen at a hi-fi show, the same Richard Vandersteen whose design criteria are driven by an insistence on maintaining the veracity of the wave form in the time and phase domains, and when I told him how much I enjoyed using the Manley Massive Passive (very discretely) in my signal chain, he explained how he sometimes employed a Cello Palette (a sophisticated preamp with parametric EQ capabilities) in his own system...
I employ the Manley Massive Passive more like a tonal contour than an aggressive set of tone controls. Don't ask me how ...every now and then I'll call EveAnna Manley to talk about the Massive Passive, and she invariably slaps the taste out my mouth ("Read the owner's manual, Chip"), so my approach to the Massive Passive has been largely intuitive, all very trial and error. In fact, I lent it to the bassist in my band to use in his recording studio for a pretty extended period of time, and only recently got it back into my reference system.
The Manley Massive Passive for this user represents Tone Controls of the Gods, and while it was not truly engineered as a complement to a high end audio home system (more like a mastering mixing super-hero), it is an unbelievably quiet, flexible performer, an exceptionally subtle musical instrument.
Jon Morstad was curious to hear how I used it, and as it proved such a lovely complement to the Bel Canto—introducing selective amplitude boost, waveform shaping and emphasis at selected frequencies—here goes.
It's hooked up to the preamp via the tapes in/out (send/receive), and is accessed via the VTL 5.5's "Tape Monitor 1" toggle switch. I employ a custom set of Acoustic Zen Silver Reference II Interconnects to connect the unit to the preamp (1/4" plugs out of the Manley to RCAs on the VTL). I zero in on a flat mirror image of the preamp sound by ear with the EQ functions defeated on the Manley, and once unity gain has been set, I introduce selective amplitude and Q at specific frequencies—the less gain the better. You keep repeating that, Chip? For sure, because I need to remind myself that we don't want to obscure all those relationships in the time domain, so we are listening more to the EQ than the system (which is kind of fun on some post-modern Pro Tools generated music where nothing ever resided in the acoustic domain). You can kind of fill in all of that lovely black space between instruments, and many of the more revealing low-level dimensional and ambient cues. To air is human, to obscure a fine line.
My imaginary template for tuning in the Manley's triode glory is, not surprisingly, an acoustic piano, so the EQ functions more like a tonal contour, allowing me to dial in a gentle tonal curve, to add a bit of big speaker fatness to the booty around 33Hz (roughly between low C/C#, just up the very bottom of the instrument at A-A#-B); then I try to bring out some subtle, selective emphasis in the lower midrange and midrange frequencies (adjacent to Middle C at 270Hz and an octave-and-a-half up at 680Hz); finally, just a dab of sweetening and presence at the starting gate of the middle treble range (which at 2700Hz is situated in the piano's top octave).
For reasons I cannot fully comprehend I employ the shelf style of boost on the lower bass-lower midrange-midrange while I employ the bell mode for the mid-treble (shelf sounds a little more subtle). From top to bottom, tweaking one frequency has a progressive effect on each successive frequency, and over time I've learned through creating nasty distortions to lay back on the amplitude so that when A/B-ing for guests, they are often hardly aware whether it is on or off. In learning to lay back on amplitude levels, the effect of the rotary Q controls (starting off in the 11:00-1:00 range as the manual suggests) seems a bit more apparent, and my choice of frequencies shapes the signal in such a way as to make things a bit more forward, punchier, fuller and sweeter, with room to slide up or down for different source materials (I especially like to put the Manley into play on analog sources, such as on a really cherry Kyocera D-810, a classic cassette deck, every inch a Dragon, which I recently copped from the "They Don't Build ‘Em Like This Anymore" aisle of Audiogon ...there, I confess), but otherwise, over time, I've found I'm basically doing little more than fine tuning the soundstage, and giving myself a limited range of frequencies to make selective boosts or cuts depending on how I want to experience source materials. And yes, dear readers and audiophile Jihadists, for most critical listening, it is obviously not in the circuit.
These parametric controls are ideally suited to the demands of mastering and mixing, but over the course of time, learning to appreciate the cool, solid command of the REF1000s, and given its mellow neutrality, I was able to zero in on more subtle, efficient ways to employ the Manley, to gently color the B&W tabula rasa these amps convey, without adding cartoon effects to the sound of the Confidence C1 mini-monitors... just enough for (here's that word again) some presence and sweetening.
Which, by a circuitous root, brings us to our final conclusions about the Bel Canto REF1000 monoblocks.
For all my enthusiasm could I imagine these amps sounding even better? Sure I can. Could they possibly be voiced with a little more ...oh, I don't know, not brightness, but a slightly sweeter, more gleaming, open, transparent presence? Maybe even a touch more punch in the lower bass, as my experiments with the Manley Massive Passive lead me to believe.
Folks, even a terrific set of amps can always be improved. Hell, when I finally purchased my review samples of the Rogue M150s (which had gone bye-bye for several months to appear at some trade shows), Mark O'Brien had apparently implemented some changes to the input stage, which made the amps' performance in balanced operation even more profoundly affecting, while making its performance in the Ultralinear mode much more on par with that in the Triode mode.
So while I dig the REF1000s big-time, and there is nothing especially muted about its performance, I could easily imagine some folks wanting less indigos and mahogany tones, more turquoise and curly maple.
But we're splitting hairs down to the sub-atomic level now. The Bel Canto REF1000s offer listeners an especially dulcet, essentially neutral balance of power and elegance that is very easy to listen to, yet can make you jump out of your chair at the drop of a rim shot. They control demanding speaker loads beautifully without imposing much of a sound signature of their own on the music, allowing you to really zero in on the kind of sonic balance that best suits you—depending on how you mix and match components and couple acoustically to your room. I would suggest that if you have a borderline hyper-analytical CD player (say like the utterly revealing Linn 1.1), which gives you a wealth of detail but maybe sits too far up front in the concert hall and could use a bit of a goose in the bass, the Bel Canto could relax things enough to let you lay back and listen, more on the mellow side of life, but with a ready supply of vivid dynamics in reserve
Damn, all that good juice for a fraction of what you'd expect to pay for your garden variety muscle amps. And when mated with some of the other fine Bel Canto source and control components, you could put together one hell of a nice system, again, for significantly less than some snooty audiophile mandarins have led you to believe is possible—leaving you more money to possibly invest in better loudspeakers, source materials or your children.
Yes, life can be good, and if I may be allowed to mix my metaphors, John Stronczer has really knocked this baby out of the park—the Bel Canto REF 1000 monoblocks have taken a gold medal in the high value/high resolution event.
PS: "A little over 6000 words represents brevity, Chip?"
[Cough] For moi? You bet. I'm built for comfort, miss, I ain't built for speed. Chip Stern
REF 1000 amplifiers
Bel Canto Design