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Positive Feedback ISSUE
SE-MKII preamplifier and NVS 572 amplifiers
as reviewed by Carl Hruza
I was quite intrigued at the prospect of spending some time with a high-end pre and power amp combination carrying the label "Made in Vietnam". It isn't unusual these days to see China as the country of origin, but so far, this is my first encounter with a product from this part of the Indochinese Peninsula. The Vietnam War destroyed much of the economy of Vietnam and it took many post-war years to pass before sufficient political and economic reforms enabled the re-establishment of friendly trading relations with the US and much of Europe. With the lifting of post-war embargoes, Vietnam 's manufacturing base has grown rapidly, as has its economy. Given our history, guess it's something of a miracle of globalization to see Vietnamese products in North American homes.
Navison Audio has been around as a manufacturing supplier to the Asian market since 2003 and functioned as a design company for three years prior to that. Navison have recently launched their product line into the US, with pricing at a point that competes squarely with the likes of Conrad Johnson, Audio Research, and Cary Audio. With a small support team based in San Jose CA, Navison Audio can provide local sales and service to the US market, while retaining the cost advantage of a manufacturing base in Vietnam.
Ben Nguyen is President-CEO of Navison Audio and is the main contact at the San Jose office for all things sales or technical. Talking with Ben I gained the impression that his company is very committed to their presence in the US. This isn't a 'toe in the water' venture to look for possible market openings; it's a full-blooded assault on the high-end market. There are dozens of amp manufacturers around today whose offerings seem to be more of a market 'probe' than the finished article—poor cosmetics, unreliable circuits, difficult to source components, etc. The two Navison products that I've been fortunate enough to have in my possession have exhibited the kind of attention to detail, evident in their aesthetic and ergonomic refinement and manufacturing fit and finish that one would expect only from the elite few manufacturers.
Navison Audio SE-MK II Preamp Navison's top of the line preamp ($4900) is a vacuum tube based, microprocessor controlled linestage, with an impressive array of user-friendly features. For two-channel functionality it is similar to my Aesthetix Calypso Linestage, offering stand-by, mute, source, volume, balance and phase control, all without having to leave the comfort of your couch. Instead of the generic, tacky, plastic remote that comes with the Aesthetix gear, the Navison has a very handsome brushed aluminum remote with a very solid and "chunky" feel to it. The unit isn't HT-friendly as evidenced by its omission of any pass-through or sub-out connections. The SE-MKII has the bare minimum of connectivity one might require, with RCA inputs for three sources and two pairs of RCA outputs.
This preamp is simply a delight to behold. From the moment I released the unit from its packaging I was taken with its attractive appearance and solid feel. The front-panel of the unit is a blend of hi-tech and traditional styling. A brushed aluminum panel houses LED indicators and push-button controls, the latter having a solid and tactile feel. The user-interface is flanked either side by very attractive Barian Kingwood panels.
At 35 lbs and 15.68D x 21.84W x 4.15H inches, this preamp is quite a handful to place and position atop the equipment rack, even for a brute like myself. It isn't the weight necessarily that makes it a little difficult to maneuver, but the physical size of the unit. This leads to one minor drawback, one that I believe to be a small miscalculation on behalf of the designers; it doesn't fit into a standard equipment rack opening and thus requires a place on the top shelf in most racks. Spinning this differently, the top shelf is really where this unit deserves to be. Navison recommend connecting their preamp to power amplifiers with an input impedance of 20k ohms or higher and remind owners via the comprehensive user manual that the preamp is phase-inverting.
An impressive resume of internal components prepares the listener for some of what's to come, not least of which are the venerable Jensen and Mundorf caps, and Riken resistors. At the heart of the unit The SE-MKII circuit employs eight vacuum tubes, all 6H1-EBs, which the manual claims offer low noise and low microphonics. With the SE-MKII connected to my Cary 2A3SE monos the system exhibited just a hint of tube hiss, just barely audible at the listening seat and insufficient to create any real nuisance factor. My speakers are horn-loaded and rated around 106db, so are highly revealing of any component noise whatsoever.
Navison, much like Cary and several other tube amp manufacturers, recommend that you source replacement tubes directly from their service office, and back-up their tube selection with the claim of an anticipated two to three years of tube-life, if the unit is used in "normal" operation. By normal Navison intend that you switch the power button off, placing the unit into standby mode after each listening session.
Sound Quality From cold, and it was cold, the unit being delivered to my Wisconsin location in April; the SE-MKII seemed to have a little too much tube bloom and midrange warmth. A little over-cooked as it were. Naturally one shouldn't listen too critically to any component that hasn't had time to fully warm-up, but let's face it; can anyone resist the temptation of taking a sneak preview of a new component as soon as it's been plugged in? After 4 hours of warm-up (the unit was a well-traveled review sample, hence fully broken-in) the SE-MKII sounded, well, quite glorious in fact. Gone was the layer of excessive warmth and in its place a wonderfully full-bodied and articulate presentation. This certainly isn't a tube amp voiced to sound like solid-state. It has all the character of a tubed component and makes no attempt to hide its vacuum-tubed virtues. However, is it possible to have too much of a good thing going on with tubes? After a week or so I decided to try to ascertain the true signature of the SE MKII by pulling the preamp and running source-direct into the Cary power amps. My Capitole MKII player has volume control in the analog domain and is a very worthy contender for a high-end preamp in its own right.
With the Navison removed from the chain, the effect was similar to that of pulling the Calypso—the sound quality deteriorated. Some would argue that a source-direct route has to be optimal, since we're removing a whole chunk of active circuitry from the signal path, circuits that must be imparting some undesirable artifacts on the sound. However, as I discovered with the Calypso, the Navison provides a safe and unmolested passage for the signal. Its presence in the signal path provides the listener with a more lively and enhanced sense of dynamic contrast, versus the more laid-back and less involving sound of running source-direct.
With the Capitole driving the Carys direct, there was a distinct loss of dynamic agility and also weight and body to the individual notes. Not just a leaner presentation, but also one that is more laid-back and less involving presentation running source-direct. Cynics would argue then that the Navison (and Aesthetix) must therefore be "adding something", which would of course be breaking the golden rule of high-end audio. I prefer to think of it this way; using a good active linestage may help to prevent the removal of information in the audio signal, rather than add to it. I believe this preventative function is achieved by the active circuitry of the preamp providing a more sympathetic matching of output and input impedances/gains between the source and the power amp - a better electrical match.
So what is the signature of the SE-MKII? To offer some comparative perspectives to the reader; before hearing the Navison I had always considered the Aesthetix Calypso to provide a near perfect balance of preamp attributes; detailed and transparent yet with the harmonic richness one expects from tubes. I like to slice my pie just on the warm side of neutral so long as I don't feel robbed of the subtle detail that might be obfuscated by an overly warm tonal balance. There's undoubtedly a conflict between having a warm, full-bodied presentation and one that allows you to hear the subtleties residing in the deeper layers of the musical event. Where I thought the Aesthetix achieved the right balance of warmth and detail, the Navison takes the warmth versus detail dichotomy and resolves it dead on—at least for my personal tastes.
So, is it possible to have a fleshed-out, scarily palpable image of Johnny Cash singing "Delia" in your room, followed by an uncanny unraveling of the micro detail in the plucking style of the late Michael Hedges? With the Navison SE-MKII preamp it is. But what about all the other audiophile measurables like frequency response, transparency, soundstage, imaging? Well, the Navison concedes just a tad to the Calypso in soundstage width. Where the Calypso releases the sound more freely from the outer speaker boundaries, the SE-MKII hangs on to it just a little. This affects perceived transparency a tad also, with the Aesthetix perhaps attaining a 9, versus the Navison's 8.5 out of 10. The Navison presentation is slightly forward of the speaker plane in comparison to the Aesthetix Calypso, the latter offering a slightly enhanced illusion of stage depth as a consequence of its more recessed presentation. The Aesthetix has a touch more energy at the top of the frequency spectrum, providing slightly more air and sparkle, where the Navison is just a little darker by comparison. With this slight top-end reticence one might expect a slight loss of image focus and definition to follow, but that is certainly not the case here. Imaging is first rate; solid, focused, palpable, without sounding artificially etched into space.
Bass from the Navison preamp is tuneful and extended with good pitch definition. I wouldn't use the word "taught", at least not in the sense we've come to expect from solid-state amplification, but it hangs together well and doesn't tip toward excessive ripeness as many tube-based components often do.
A couple weeks into my time with the SE-MKII I took delivery of a pair of Acoustic Zen Silver Reference II interconnects. The idea was to switch out the HT ProSilway III hybrid, in favor of the full silver cable, to see if a little more could be extracted from the higher frequencies. With the AZ Silver Ref's in place between source and pre, the higher frequencies opened up a little. Gone was any sense that ambient cues were being curtailed and the presentation of higher frequencies stepped more towards the extension and air of the Aesthetix. Yet oddly enough the amplitude of the lower frequencies seemed to reduce noticeably, requiring some adjustment to the bass crossover. The point being, as with any highly resolving component, cable choices can certainly have a significant impact on the overall presentation.
The above are merely observations on single elements of the sound of this preamp and should not be construed as anything meaningful or definitive when taken in isolation. The whole point of a quality component is to deliver the heart and soul of music, and the Navison Audio SE-MKII preamp excels at reproducing music across the entire musical spectrum with its heart and soul intact.
Where some preamp designs seem to go all-out in favor of excelling in one particular area, the SE-MKII seems to get it right across the board. Dynamic and detailed, yet able to deliver these attributes with the perfect amount of "flesh on bones"—you won't hear a stripped-down skeletal version of the musical event with the Navison.
Enter the NVS 572 monoblocks. ($6900 pair) Just when I thought it was safe to answer the door again, the FedEx driver rolled up with another two large crates. Just like the SE-MKII preamp, the 572 amps were impeccably packaged, double-boxed in sturdy shipping cartons offering damage resistance of a standard to frustrate even UPS on a good day. (I'm sure UPS would still loose them).
Fit and finish of the 572 is superb, with the same matching exotic wood trim as the SE-MKII, this time with the added embellishment of engraved lettering deep into the face of the dark wood surface.
Removing the first amp from its carton, I prepared myself for the weight to be distributed more under the transformer cans, thus requiring a front to back grip and not side to side. Surprisingly, the weight, an ample but not excessive 33LBS, was fairly evenly distributed front to back. A quick rap on the transformer cans produced a fairly hollow sound, confirming my suspicion that the extremely large cans are merely cosmetic covers for much smaller transformers.
Setup of the 572 amps was a breeze, they replaced my Cary 2A3s, also monoblocks, so no re-cabling was necessary. Sitting on AudioPoints spiked into extremely heavy Target R3 stands, in turn spiked into the floor via more AudioPoints, the amps looked very classy flanking their SE-MKII sibling.
The NVS 572 is a single-ended Class A Triode, pushing out a useful 15 Watts per channel from a single 572 Svetlana tube, developed from the 811 class of transmitter tubes renowned for their excellent linearity. Key performance parameters taken from the Navison website: input sensitivity is rated at 2.5 Volt for full output, input Impedance is 100 K Ohms, frequency Response 15 Hz to 20 KHz, and hum/noise specified at -75 dB below full output.
I haven't rolled many power amps through my system of late. The most recent to take the place of my little Cary 5-watter's for a while was a pair of push-pull Jadis JA30 mono's. The Jadis gear gave me a flavor of what a high-powered push-pull design could accomplish in a 106db system, which on paper at least doesn't require more than the little Carys have to offer. The Jadis brought to the party two notable elements, both of which the Cary's lacked: upper bass/lower midrange impact—and tube noise. The NVS 572s were quiet in my system, but like their stable-mate the SE-MKII preamp, they were not dead quiet. With the 572/MKII combo there was audible tube noise at the listening seat, more so than with the Calypso/Cary combo, but much less so than with the Calypso/Jadis combo. One of the advantages of a basement listening room, at least in my situation, is the absence of any distracting ambient noise - no refrigerators, furnaces, neighbors etc, so the slight tube-rush was a little disconcerting at first. Given more time or the potential of future ownership, I might have dabbled with PCs or earthing arrangements to try to abate the unwanted background hiss, but it wasn't really distracting to the point of driving me to such measures.
So how did the 572 amps sound in my system? These power amps are certainly cut from the same sonic cloth as the SE-MKII pre. Their focus is to connect the listener directly with the music and to avoid shifting any emphasis onto the sound of the equipment. Dynamic, bold, full-bodied and detailed, are terms that best describe the sound of the 572s in my system. Again, as with the MKII preamp, Navison seems to have mastered the art of blending detail with a tonally warm and harmonically rich presentation.
Initially I had the notion that perhaps the combo tipped the balance a little too much towards the warm side of things. The simple acid test for determining if a component has crossed the line from having a harmonically rich and naturally warm presentation, into a place that might be described as "syrupy" or bloated, is to play a few cuts of more complex music. The wonderful recording of Bach's Passion on the Decca Label (sub-titled The Passion of Christ As You've Never Heard It Before) took its turn in my CD player. I'm not generally a fan of choral works, but highlights from St. Matthew Passion featuring the Chicago Symphony Chorus invariably seem to find their way into any critical evaluation session of late. Listening for any loss of separation where performers blend together and lose their individual space, I can honestly say that the Navison combination never crossed the line into excessive midrange bloom; in fact it walked the line better than any other pre/power amplifier combo I have heard in a long while.
The extra power from the 572 (15-watts, compared to the Cary's 5) certainly delivered more dynamic contrast and visceral impact; quite startling on certain percussive oriented tracks. The excellent ECM recording of Manu Katche's Neighborhood sparkled with energy, the bite and attack of Katche's stick-work popping out from the soundstage with lifelike impact and presence. The enhanced sense of dynamics and nicely focused image placement created a more dramatic dimension to the presentation than could ever be solicited from the 5-watt Carys.
The extra drive from the 572s also paid dividends when watching concert DVD's on the large screen. When forced to play cuts from the Godsmack Changes DVD, by people much younger than myself, I was quite taken with the systems' ability to create a soundfield that enveloped the listener and pressurized the room with sound level peaks measured in excess of 106 dB, without any hint of compression or strain.
On the excellent David Gilmour in Concert DVD, the Navison combo captured the acoustic space and delivered the event with a degree of palpability and presence that I haven't heard from my system before. More complex tracks from this DVD, such as the Division Bell cut "High Hopes", retained the individual space of instruments on the stage, layered-in the backing vocalists with sufficient depth, and relayed the liveliness of the acoustic space without any discernable additions or omissions. With the volume set quite high, the stage never showed any sign of reducing in scale or becoming homogenized as the track evolves into its instrumental crescendo. In the interests of fairness I must draw readers to the fact that my horn towers, as driven by the 572's, run only down to around 150Hz, with bass duties picked up by a dedicated bass amp from 150Hz and lower. So while I am able to assess the bass performance of the preamp, I can't comment specifically on what the NVS 572 is able to accomplish in the nether regions.
The Navison Audio NVS 572 and SE-MKII preamp are top-class components designed to provide complete musical satisfaction ahead of all else. Where some components thrust detail in your face in a way that draws attention to the equipment, the Navison allows you to bask in the glory of the music without distraction. Their harmonic richness and inner light, the kind that can only come from tubes, creates a perfectly illuminated portrait of the event and at the same time presents music with true to life presence and impact.
There's another aspect of the Navison equipment, even more subjective than the above, but worth mentioning anyway—pride of ownership. The equipment is so well built, so stunning to look at, and so ergonomically friendly, that you just want to place it in the most prominent position in your equipment rack and admire it.
Who should consider seeking out an audition of Navison Audio products? Well, I can still envisage the person who thinks audio equipment is merely a tool to help analyze the individual notes of a performance, and not a medium for transporting you to a musical event. I've met this person so I know he exists. Anyone who's in it for the music and not just the gear (and it's ok to dig both) should check out the NVS 572 power amps and the SE-MKII preamp. If I could afford a $12,000 addition to my system I would be quite comfortable making an investment in Navison Audio, one that I'm quite certain would provide me with the highest level of musical satisfaction for years to come. Carl Hruza