The only promise that BAT’s VK-655SE does not fulfill is the company’s claim that it has enough energy storage to “to lift most speakers over one meter off the ground.” Even at earsplitting levels, neither the 610-pound GamuT S9 nor the 253-pound Dynaudio Evidence Platinum speakers move ever so slightly off the ground.

What the VK-655SE does deliver is musical accuracy, exquisite tonality and bass control. With 1,800 joules of power available, the $16,500 VK-655SE controls the lower half of the frequency spectrum in a way that precious few amplifiers can muster at any price. For the non-electrical engineers in the audience, a heart defibrillator uses between 200 and 400 joules at its maximum setting, so while the VK-655SE won’t lift your speakers off the ground, if you connect your speaker cables to your chest and crank it up, it will probably lift you a meter off the ground. Maybe that’s what they meant.

Speaking of weight, the VK-655SE weighs 120 pounds, so make sure your back and whatever stand you plan to place it on can withstand that much heft. Popping the lid reveals a pair of monstrous heat sinks, power transformers and capacitor banks. The VK-655 is available in all black (as shown here) or with a black-and-silver aluminum faceplate. In the future, BAT will also offer all silver, so if that is the aesthetic you desire, its on the way. Fully intended for use in an all-BAT system, the VK-655SE offers only balanced XLR inputs—though we found that the VK-655SE works equally well with Pass, ARC, Nagra, Simaudio and Robert Koda preamplifiers; all were used in a fully balanced configuration.

Let’s Roll

The VK-655SE is special straight out of the packing carton. Taking the hot-rodders credo, “If you want it to run hard, you have to break it in hard,” I immediately reach for Metallica’s album Kill ’Em All and play “No Remorse” at near-Armageddon levels. Even during a brief stint of driving the Dynaudios to almost 120 dB peaks, the BAT doesn’t strain whatsoever, with the raw power of Metallica thoroughly communicated. While I can’t imagine needing more power, you can turn the VK-655SE into a monoblock amplifier and get a bit more, going from 600 watts per channel into a 4-ohm load to 700 watts per channel. (The VK-655SE produces 300 watts per channel into an 8-ohm load as a stereo amp, and 400 watts as a monoblock.)

For those scoffing at the idea of paying twice as much for only 100 more watts per channel should remember that higher fidelity means gaining control, not just getting louder. This is because doing so doubles the current output, giving the monoblocks the ability to control difficult loads more effortlessly. Having twice as much power on tap will make those monos run even more effortlessly than running them in a stereo configuration, translating into greater dynamic range and an even quieter background – 6db according to BAT. I notice a similar effect going from a single Burmester 911 MK3 power amplifier to a pair of 911 monos. It is not subtle. I’ll stick my neck out and suggest a pair of mono VK-655SEs will achieve the same results.

Experience with BAT’s past products featuring the Super Pak upgrade (the company’s own variety of oil-filled capacitors to help facilitate all this power storage) showed that these components take a while to sound their absolute best—anywhere from two to 500 hours. The higher current flow of large power amplifiers makes the process a somewhat speedier one; the preamplifiers seem to take longer.

Slightly edgy at initial turn-on, the VK-655SE sounds more open, natural and relaxed in the upper register after about 48 hours of constant play, with a subtle smoothing as the hours rack up, but not as dramatic as the change during the first couple days. For the crabby audiophiles in the crowd who do not believe in component break-in, I highly suggest borrowing a pair of identical amplifiers, running one for a few hundred hours while you leave one in the box for that period of time and then compare the two. There is an unmistakable difference between the amplifier with hours on the clock and the one left in the box.

BAT’s Geoff Poore makes it a point to stress that they strive for “dynamic linearity” in their designs. A big part of this comes from their eliminating negative feedback in combination with an unlimited, unregulated power supply – adding to the jump factor that BAT amplifiers are famous for. It’s also one of the main reasons this huge amplifier exhibits the dexterity of a much smaller amplifier. Poore reminds me that “using only two gain stages in the VK-655SE eliminates coupling effects between multiple gain stages, further reducing the amount of image smear and degradation that comes with a more complex design.”

Where some power amplifier manufacturers claim a dual-mono design, BAT takes it to the extreme. In addition to separate power transformers and power supplies for each channel, the VK-655SE even uses separate power cords and receptacles for each channel! Should you have access to dedicated power lines, I suggest trying separate power lines on separate circuits for each channel. My curiosity with the VK-655SE is satisfied plugging each channel into separate 20-amp circuits. Of course, you don’t need two power lines for the VK-655SE, but with two separate mains fueling the fire at ear-splitting levels, the amp exhibits even more ease. About 95% of the time, you’ll never notice it, but if you really like it loud, go for separate AC circuits to power each half of your VK-655SE.

A Quick Comparison

If you believe all amplifiers have the same sound, stop reading now. Though the world’s top solid-state amplifiers are starting to sound more similar than disparate, differences in sonic character still exist. Side-by-side comparisons to a few of our regular amps reveal the BAT to excel in speed, dynamics and bass weight. The Burmester and Pass amplifiers in our stable are slightly warmer tonally, while the big Simaudio MOON 880M monos sound as natural as the BAT, but more bottomless in power capability—albeit at a higher price than a pair of VK-655SEs. It’s almost like comparing an Audi to a BMW or a Mercedes; all are excellent, though they go about delivering the goods in a slightly different way.

None of the speakers we have on hand present a challenging load to the mighty BAT. The current-hungry Magnepans and even our vintage Acoustat 2+2s, which have only an 82 dB sensitivity rating and are not much more than giant capacitors placed across the speaker terminals, do not diminish the amp’s performance in the least. Where some amplifiers can be speaker-dependent and struggle at times, the VK-655SE effortlessly powers every speaker we have on hand with ease.

Part of the neutral sound quality of the VK-655SE can be attributed to its use of all N-channel MOSFET output transistors. The N-channel MOSFET has a higher electron mobility, which makes amplifiers with them appear to have more transient speed than amps with mixed devices. Cursory research on the N-channel MOSFET implies that the N-channel device also has a wider range of operation where it acts like a triode tube—another great thing to have in a power amplifier. Techie bits aside, this amp succeeds brilliantly, especially for $16,500.

Bigger Is, Well, Bigger!

Some arguments in audiophile circles—about the quality of the first watt and that, because of their inherent complexity, higher-powered amplifiers are not as pure as low-power amplifiers in design and thus sound—don’t always hold true. Those arguments certainly don’t hold true in the case of this amplifier. While I’ve heard excellent examples of both low- and high-powered amps, I still tend to prefer the effortlessness of a high-powered one, even at low volumes. The VK-655SE takes a novel approach, featuring no negative feedback and only two gain stages in the entire circuit. In the same way that some large speakers manage to disappear in your listening room like a mini monitor, the VK-655SE has the sheer might of a large amplifier and the nuance of a small power amplifier.

Listening to acoustic instruments highlights the character of the VK-655SE. Its enormous power reserves might not be noticed with less-demanding fare, but the instant a drumstick hits a cymbal or the string of a standup bass is plucked with force, the boundless reserves of this amplifier deliver the dynamic swing required to convince your auditory system that perhaps you’re not listening to recorded music at all.

This is equally true when reproducing a vocalist with a wide range. Whether it’s your favorite opera or Prince, the VK-655SE’s instant delivery comes through free from the stress associated with lesser amplifiers unable to keep up—and this ability is too often overlooked when jumping on the low-power bandwagon. Simple as it might seem, a big, well-executed amplifier just sounds bigger and has a lack of restraint that further contributes to its overall neutral character.

There was nothing that the VK-655SE couldn’t handle effortlessly during this review. In the realm of the reference speakers at my disposal—all with sensitivity ratings of 87 to 90 dB—I can’t imagine ever needing more power than this amplifier delivers. BAT gear is known for its fantastic build quality and excellent secondary-market value, so for an amp at this size and price, I also can’t imagine ever needing another one once you’ve stepped up to the VK-655SE. Unless of course you need a second one.

BAT VK-655SE power amplifier

MSRP: $16,500

www.balanced.com

PERIPHERALS

Analog Source	AVID Acutus Reference SP turntable    TriPlanar tonearm    Lyra Atlas cartridge
Phonostage	ARC REF Phono 2SE
Preamplifiers	Robert Koda K-10    ARC REF5 SE    Pass Labs Xs
Digital Source	dCS Pagaini Stack    Simaudio MOON 650D
Cable	Cardas Clear
Power	IsoTek Super Titan

The VK-3000SE from Delaware’s Balanced Audio Technology (BAT) is a vacuum-tube linestage and a solid-state amplifier rolled into one. The latter offers 150 watts per channel into 8 ohms and twice that into 4 ohms. For the preamp section, BAT utilizes a pair of Russian 6H30 valves, which are concealed inside the unit. Some refer to these military-grade tubes as “super tubes” for their longevity and durability; they’re also alleged to have a whopping 10,000-hour lifespan. In the unlikely event of a bad tube, BAT stands behind them with a one-year warranty. (The VK-3000SE itself comes with five-year warranty.) The unit weighs in at 50 pounds and the chassis measures 19 by 5.75 by 15.5 inches. It’s priced at $7,995, which is pretty reasonable considering the amp’s broad capabilities.

As you might guess by the company’s name, the VK-3000SE’s internal circuit topology accommodates a fully balanced signal. The back panel offers a combination of three single-ended RCA inputs, two balanced inputs and an RCA tape out. Metal speaker binding posts accommodate many connection options. Keep in mind that the posts are quite close together, so large speaker cables with spade connections like mine require some finagling.

In addition to the standard linestage capability of the preamp section, BAT offers a pre-installed MM/MC phonostage with the associated outboard inputs as a $1,000 upgrade option. Users have an option of a 48 or 55 dB gain, the latter being the default. Load-wise, the phono card is factory set at 47,000 ohms, but it can be adapted for other cartridges as needed. Users can make these changes themselves by removing the unit’s cover and following BAT’s instructions. The standard load works quite well with my cartridge, a Dynavector 17D3, so I didn’t make further adjustments.

Clean Design

The VK-3000SE offers a clean, elegant external design. Our sample unit sports an anodized black finish, but silver is also an option. The hefty, metal remote control has a similar finish. The chassis’ subtle curves give the amp a sleek, modern appearance. To help keep the unit cool, which is especially important given the hot tubes within, BAT utilizes a top panel with small ventilation slits at the outer edges and holes down the center in an hourglass shape.

Once powered up, the amp’s front-panel vacuum fluorescent display (VFD) shows the input choice and volume level. The font is large, blue, and very visible—it’s easy to read from my listening seat 9 feet away. For those who prefer darkness, the remote’s display button will variably dim or turn off the VFD.

A minimal number of small controls on the front panel disguise the versatility within. The visible buttons include power, mute, input, phase, mono and function, the latter of which allows access to an on-screen menu. And of course, there’s a beefy volume knob that goes from 0 to 140. According to Geoff Poore, BAT’s sales manager, the numbering scale represents a 70 db range, in half db increments. He goes on to mention “There are two other volume “scales” that can be used in the 3000SE: “DBM” and  “DBU”.  The unit comes with a more understandable (for consumers) “CNTS” (counts) scale.  Broadcast and recording facilities are more likely to use “DBM” (-70 to 0) or “DBU” (-50 to +20).  One may preset any of these different scales in the set-up with the “function” button while cycling through.  We are very proud of the sophistication and accuracy of the volume control in the 3000.”

When toggling through the input options, you’ll see that the VFD has them listed as CD, tape, aux and so on, though the owner can modify the labels. Relabeling the third input as “iPod” proves very easy. Once programmed in, the amp stores these labels in its memory and remembers them even if it’s powered down and unplugged.

The function button is similarly flexible; pressing it reveals several user-selectable options for the selected input. Users can adjust balance, phase, mono/stereo and display mode, and select fixed, relative and maximum volume to equalize input sources and to avoid an inadvertent sound blast. To exit the menu, just hold the function button for two seconds. Most of this functionality is also accessible via the remote.

Up and Running

Setup for the single-box unit is very straightforward—just connect sources and speakers and you are ready to rock. Pressing the power button puts the VK-3000SE into a muted tube-warm-up mode; after a minute or so, a quiet click indicates the amp is ready. Pressing the button again puts the unit into a low-power standby mode, with the tubes remaining engaged. Holding down the power button for a couple seconds shuts down the unit completely.

Testing both the single-ended and balanced connections with my DAC, I find that they sound similar but have some subtle differences. The XLR connections do offer a bit quieter background, providing a little more sonic detail and nuance, and the presentation is a little more up-front. If you have the option of balanced connections, they are the way to go.

Across the frequency spectrum, VK-3000SE leans a bit to the warmer side of neutral in my system. Pitch Black’s album Rude Mechanicals provides a helpful test. The bass presentation is more relaxed than punchy and the amp has no trouble making very low frequencies known, but they never overwhelm the mix.

Extremely revealing components have a tendency to make the listener wince when playing some female vocal recordings; pleasantly, the VK-3000SE does not. Throughout Sia’s cover of “I Go to Sleep,” vocal crescendos project little stridency, despite their power. Also, as I notice in the cymbal shimmers on other tracks, the amp has a slight tradeoff of sonic realism for a touch of veil, but a degree of euphony in some circumstances is welcome. Balanced connections prove more revealing, so users should experiment with interconnects to find the sonic balance that works best in their system.

The amp’s ability to portray both a vertical and horizontal soundstage is fantastic, regardless of source material. Music extends beyond the speakers to the extreme left and right and from floor to ceiling, though front-to-back layering is not a strong point. The VK-3000SE does make it easy to pick out individual elements of a song, but it’s not a fully convincing reproduction of a live performance when band members are scattered across the front and back of the stage.

Putting the phonostage through its paces, I soon find that there’s a lot to enjoy. Analog and digital sources have similar sonic signatures through this amp, but the phonostage offers a greater sense of ease and naturalness. Vocals, like those on Daft Punk’s “Instant Crush,” move forward in the soundstage, enhancing the VK-3000SE’s front-to-back presentation. Some of that benefit, of course, is due to the analog source, but the quality of the analog reproduction is strong evidence of the effort and quality that BAT put into the unit’s phono card. It would be a challenge to find a single-box phonostage of this quality for the amp’s $1,500 phono add-on. The VK-3000SE demonstrates the synergistic value of an integrated audio solution.

Final Score

While $8,000 is a substantial investment for any piece of audio gear, it’s important to frame this product in the context of what you get for that price. You could spend a lot more money for individual components that deliver greater sonic nuance, layering, and air around each musical element, as well as a more realistic-sounding reproduction of a live concert. Of course, with added components, an owner also needs to consider the cost of extra interconnects and power cords.

The VK-3000SE is both a great preamp and a great power amp, and with the optional (and fantastic) phonostage, it’s a versatile, compact, and great-sounding piece of gear. If each of its elements were sold as individual components, the combined price would certainly be higher than the cost of the single unit, and it would be tricky to find separates that complement each other this well.

Having plenty of power and multiple input options, the VK-3000SE offers a turnkey solution that will mate well with many sources and speaker types. With a five-year warranty backing it, this is a component you’re likely to enjoy for a long time, even as the other gear in your audio arsenal evolves around it.

Additional Listening

By Jeff Dorgay

Having been such a big fan of BAT gear over the years, I had to hand the main review over to Rob—partly to share the excitement of the brand (with which he’s had no experience) and to deliver a more impartial review. Firing up the VK-3000SE to perform break-in duties is like putting the keys in a Porsche 911, in the sense that everything is where I remember it and, regardless of vintage, the overall ride is similar—just as the dynamic sound of BAT is like taking an old friend for a test drive.

While BAT has made a name for itself based mostly on the reputation of its fine vacuum-tube gear, the company has always made great solid-state power amplifiers, which have not always received their fair share of (well-deserved) praise. I have always loved the combination of a solid-state power amplifier and a valve preamplifier, so the VK-3000SE is right up my alley.

As much fun as modestly powered tube amplifiers are, 35 watts per channel limits your speaker choices too much, in my opinion. But 150 wpc is just right for all but the most inefficient speakers. Everything at my disposal—from the 90-dB-per-watt KEF Blades to the 84-dB-per-watt Harbeth Compact 7s—proves a good match for this amplifier, with nothing running out of steam until I crank the volume to beyond brain-damage levels.

A side-by-side comparison to another favorite, the Simaudio MOON 600i, is enlightening. Both amplifiers are similarly priced (though the MOON does not include an onboard phonostage option), yet the MOON is all solid state. Those preferring a slightly more neutral, even a touch punchier sound and who don’t care about the phono might prefer the MOON. Personally, the VK-3000SE has that combination of solid-state grunt and a touch of tubey warmth in an ever-so-slight way that is not veiled, colored or slow.

The 6H30 is a very dynamic and powerful tube, sounding nothing like, say, a 12AX7. And BAT built its reputation around this tube, and the company implements it like no other. Whether you’re blasting AC/DC, Coltrane or Coldplay, this amplifier offers a lot of inner detail and timbral purity in spades.

As good as the onboard phonostage is, choosing it will ultimately be the limiting factor for the hardcore vinyl enthusiast. But again, it’s damn good for a thousand bucks. If you are primarily digital and just dabbling with LPs, it’s fine; grab your favorite $2,500 table/arm/cartridge combo and call it a day. However, if you’re more of an analog lover or plan on serious analog upgrades in the future, order your VK-3000SE without the phonostage and go for BAT’s awesome VK-P6 instead. (We will have that review shortly). You’ll be glad you spent the extra dough. The VK-P5 was a class leader and the P6 promises even more performance for around $3,500.

High-performance integrated amps continue to be popular for the audio and music lover who wants world-class performance without buying a rack full of components. The VK-3000SE is an excellent choice, should that be your cup of tea. This is certainly one I could retire with happily ever after.

VK-3000SE Integrated Amplifier

MSRP: $7,995 (plus $1,000 for the optional phono section)

Balanced Audio Technology

www.balanced.com

PERIPHERALS

Digital Sources	HP desktop computer with Windows 7    JRiver Media Center 19    Light Harmonic DaVinci DAC    Audio Research CD3 Mk2
Analog Source	SME 10 turntable with Dynavector 17D3 cartridge
Preamplifer	Coffman Labs G1-A
Amplifier	Mark Levinson No. 335
Speakers	Piega P-10    Sonus faber Olympica III
Cables	Jena Labs
Power	Running Springs Audio Haley    RSA/Cardas Mongoose and Golden power cords   Shunyata Python Alpha power cord
Accessories	ASC Tube Traps    Cathedral Sound room-dampening panels    Mapleshade Samson racks    Coffman Labs footers