Product Review - Balanced Audio Technology VK-6200 Multi-Channel Home Theater Power Amplifier - September, 2001
Power Output: 200 Watts at 8 Ohms, 400 Watts at 4 Ohms for Each Channel
THD: < 0.1% at Full Output Into 8 or 4 Ohms
Frequency Response: 2 Hz - 200 kHz (no tolerance given)
S/N Ratio: > 96 dB
Dimensions: 10" H x 19" W x 23" D
120 Pounds in Base Configuration (Two Channels)
140 Pounds (Three Channels)
160 Pounds (Four Channels)
180 Pounds (Five Channels)
200 Pounds (Six Channels)
MSRP: US$5,000 (Base Configuration, Includes Two Channels)
US$1,250 Per Additional Channel.
Introduction - Gargantuan
I remember almost literally jumping for joy when JJ, our Editor-in-Chief, said "My plate's too full, why don't you do the review of the Balanced Audio Technology (a.k.a. BAT) VK-6200?" Was he kidding? Need he ask? The only question I had was, "I wonder how soon they can get me one to review?" This was before the herniated disks and pinched nerve came in late last year. Patience is a virtue, and after the retail channels were filled with products, the time came for Secrets (and me) to get our review sample.
The BAT VK-6200 is a physically enormous amplifier. The chassis, with no channel modules, weighs in at a somewhat hefty 80 pounds, and each channel module tacks on an additional 20 pounds to that total. It's the first time I've had an amplifier shipped to my home on a pallet, and it sat locked in my garage for a few days until I could gather the right resources to move it up into my home theater room.
Given that my review sample (five channels) weighed 180 pounds, there was no way this could be moved around casually, so I placed a call out to the folks at Sound Anchors -- they were kind enough to loan me one of their amplifier stands on casters, which quickly became christened . . . The BATmobile! Many thanks! This made the amplifier movable so I could rearrange my listening room as necessary without worrying about a hernia or another back injury.
Some of the images I'm using come from BAT's images library. I found it very difficult to get the lighting acceptable to take photos of this marvelous, though large, amplifier.
As pictured above, you can see the front panel is handsomely finished, sporting a black and silver faceplate capped by the familiar Balanced Audio Technology logo perched on the top of the panel, centered. The rest of the amplifier chassis is matte black, and (like atoms) is mostly empty space until you addy more channels. The top, sides and bottom are perforated and/or slotted to permit the free flow of air around the amplifier and eliminate the need for cooling fans.
As hot as this amplifier might get, the huge area for air flow, coupled with generous heat sinking of the amplifier modules means the chassis itself barely gets above warm to the touch, even during the hottest days of the summer. The area surrounding the amplifier was always a few degrees warmer than ambient, indicating a fair amount of heat is being dissipated. Too bad the VK-6200 wasn't my companion for the cold winter months instead of the hot summer!
This (photo at left) is the top of the amplifier, and you can see (sort of) the amplifier modules as well as all the cutouts for airflow.
The side panels have cutouts for airflow as does the bottom of the amplifier (not shown). Only the front and back panels aren't open for air circulation.
If you demand an absolutely dark HT room, you'll need to talk with BAT about disconnecting LEDs. The Front panel has a lovely blue power-on LED, and a fault indicator which flashes on and off when a channel failure is detected. Each amplifier module has two green LEDs and a single red fault LED. These are visible in a darkened room through the chassis cutouts.
Besides the physical enormity of the chassis, the modules themselves are enough to make the audiophile salivate. Each module contains an 800 VA transformer, which allows the amplifier to double down into a 4 Ohm load. Additionally, there are 8 bipolar output transistors per channel, and 40,000 µF capacitance per channel. With ± 75 Volts on the capacitors, this gives 225 Joules of energy storage for each channel. If you have five channels, that is 1,125 Joules for the entire amplifier, one of the largest in the industry. With that kind of power supply, each channel could probably put out 400 watts into 8 Ohms on a transient basis. Only a very small amount of the power is in Class A (about 1 watt). The output stage is not a balanced circuit, although the amplifier has balanced inputs. No global negative feedback is used.
To install a module is not for the faint of heart, and just to remove the cover (for the top and sides) requires taking out 20 screws, and they're Torx T-20s, so if you're going to install a module yourself, plan ahead. You need to remove the top AND bottom covers to replace or install a new module, and undo another series of screws to remove the top plate from the amplifier modules, and also to remove the screws that lock the module to the bottom of the chassis. Two connections to the front panel are all that are required to get the channel rolling.
The back panel, in an unusual design for BAT amplifiers , allows for switchable selection between Single-Ended and Balanced inputs. In my system, I obtained best results using Balanced inputs. If your preamp/processor doesn't have balanced outputs, don't fret! You still get excellent results from the single-ended inputs (via our old friend the RCA connector). The VK-6200 supports a 12v trigger for power up via the 1/8" phono connector, and can also pass a 12v trigger signal on to other components.
Speaker connections are through a single set of gold plated, heavy duty binding posts for each channel. The posts are quite well made, and look as though they might be sourced from Cardas.
I tried shotgun bi-wire (with a dedicated wiring run) to each speaker binding post using spades on one set of cable and bananas on the other. Since this review isn't about the benefits of bi-wiring and the options available, I'll just say my results were best with the shotgun bi-wire approach.
I started my listening sessions with stereo music. I have the greatest familiarity with this format, so am able to focus my most critical ear here.
Those who know me, realize that I'm a fan of planar (ESLs and ribbons) transducers. They have an openness and clarity that few dynamic (cones) transducers can deliver. When I started working with the VK-6200, it was clear very shortly out of the box that things weren't quite the same anymore. In trying to avoid the clichés, and will say that the open sensation I heard from the system was very like the time I went from dynamic to planar loudspeakers. Note also that using planar speakers with an amplifier puts the amplifier at a disadvantage because they tend to have low impedance and only modest sensitivity. So, when an amplifier does well with such speakers, it is even more impressive.
Disc after disc was placed into the spinner, with uniformly excellent results. This doesn't mean the VK-6200 is sugar coating the output. On the contrary, it's a very authentic presentation. My bad recordings sound bad. My great recordings sound great.
An example of a bad recording that I enjoy is a re-mastered version of Styx' Greatest Hits. The recording quality is fairly dreadful, but my formative years of that era developed an affection for their music. Without disguising the fact that this is a lousy recording, I had a much clearer "Grand Illusion" going on in my room. Lead vocals from Tommy Shaw and Dennis DeYoung had quite a bit more open quality to them than I had experienced in the past. Perfect? No. Still pretty noisy, and lacking in clarity. More listenable and enjoyable? Indeed. Sometimes you stick a disc in because you like the tunes!
Some other recordings that exemplify this openness include a sampler disc from Audionet in Germany. This disc contains 7 or 8 tracks recorded in 24 bit/192 kHz DVD-Audio. A rare treat that is, and with my system prior to the inclusion I was startled by the sonics of this disc. Imagine my surprise when the VK-6200 started to show me even more improvement with DVD-A, especially at its highest encoding rate, over traditional compact discs. It's a jazz quintet, with Vocalist, Tenor Saxophone, Piano, Bass and Drums. This singer has a very unusual accent, so I wondered if she was singing phonetically. Maybe so, as some of the phrasing was a bit unusual. Regardless, the illusion of reality was quite convincing.
At times, I'd keep the music going and head into the kitchen. Even outside the room, the clarity and openness of this amplifier was nothing less than first rate.
My favorite selection for showing the capabilities of a multi-channel setup is Blue Man Group's DVD-Audio disc, mystically titled "Audio". Two tracks running one after the other, PVC IV and TV Song are both superb for showing the ability (or lack thereof) to deliver both transient dynamics (via all the percussion) and dynamic contrasts. The tracks start slowly and build, build, build to their conclusions. You're immersed on the stage with the musicians and you've got PVC instruments (tubulums and PVC equivalents to the marimba) drums and guitars. This recording is dynamic as all get out, and the VK-6200 doesn't come up short. It has to be the spaces in between the notes during the higher SPL sections that helps this amplifier deliver the dynamics so well. You get all the contrasts and then some. It's as if another letter at each end of the volume scale that musicians use (p (piano) for soft, f (forte) for loud) is made available. Wow!
Stick a film into the silver disc spinner, and try the opening battle scene for "Gladiator". Oh my word! Dynamics everywhere. The horses, the metallic clangs of sword on sword, the mechanical sounds of the catapults being loaded. The whistle of arrows through the air. There's a battle all around you, and you want nothing more than to duck for cover. I'll talk about this aspect later.
So far, I've been talking about the big dynamics. Range and transients and all that, but there's more to the world than just the big stuff. What about low scale dynamics, the difference between an accented note, and a regular note? Diana Krall's "When I Look in Your Eyes" has lots of little dynamic points of interest, and take for instance the track, I Can't Give you Anything but Love. This is a piano, guitar, drums trio (with Diana on vocals naturally). If you listen to the guitar chorus taken by Russell Malone, he's mixing mostly 8th notes with 8th note triplets throughout. You get an excellent feel for the rhythmic punctuations of the modern swing style.
This is going to sound like a bit of jazz education, so if you want to skip to the next paragraph, feel free. If we split the two halves of the beat up, the bottom half (on the beat) is slightly recessed, and the top half of the beat is slightly emphasized. So, it looks something like this in a run of 8th notes one and two and three and four. These little emphases on the top half of the beat are what gives the music its rhythmic impetus. In the triplet runs, the emphasis is still away from the beat. It's these small scale dynamics rendered clearly that separate the good from the great. Here the VK-6200 does an exceptional job of delivering.
To make the Home Theater or multi-channel music experience complete (at least to me), it requires the ability to draw you into the experience, be it the immersive mix for a DVD-A (don't have multi-channel SACD yet!), or the surround sound track of a film. The key is you feel inside the movie or on stage with the orchestra.
I am undoubtedly in the minority by finding immersive mixes to be more involving than traditional stereo mixes. Many feel that this is an unnatural presentation - I happen to enjoy that each speaker delivers less of the load and if I want to focus on a particular aspect of the recording. It's easier to sort out what I want from the less sparse information in an individual channel.
What do I mean when I say "immersive", or when I'm talking about involvement? We'll use the Big Phat Band's "Swinging for the Fences" DVD-Audio disc as an example. Here's a disc where the entire band is surrounding you. The perspective is as though you're a soloist near the rhythm section, and you get the various sections in different locations of the sound stage. Track 1, Sing, Sang, Sung features the fabulous clarinet chops of Eddie Daniels taking a turn at the soloist mic.
I've drawn the soundstage (diagram at left) so that you can see how they've got the band laid out.
To say this is an aggressive use of surrounds is an understatement, but to me it's excellent. I can see the various sections of the band front to back and side to side, and it's a very expansive, wide open sound, with each instrument given more of its own space within the mix.
Very well done!
There's a stereo (two-channel) version of this, and the sonics (and the mix) are tough to go back to after hearing this particular perspective to me.
There are some other recordings out there that I used, like Glen Philipps' new "Abulum". Track 3, Back on my Feet is kind of a "down" song, and near the end of the track, you hear Glen singing harmony "back on my feet". It's surrounding you, trying to get you the message of a sliver of hope out of a really tough time. Kind of interesting. Another good recording worth checking out.
So far, you'd think all I did was listen to surround material, but this was decidedly not the case. The VK-6200 (not surprisingly) is equally adept at handling two-channel stereo as it is surround. No compromises are audible in the output of the amplifier. Let's talk about subtleties here. Sometimes vocals are the best material to bring out the ability of an amplifier to provide a convincing illusion of reality, and really draw you into the performance. So I queued up, A Nightingale Sang in Berkeley Square from the Manhattan Transfer's "Best of" disc. Each vocalist and their individuality is preserved across the front soundstage, while never losing the blend that they've worked so long and hard to achieve. This is a capella singing done by some masters, and the last chord which evaporates in the room as they release the chord is enchanting.
So what about films? We have home theaters because we like films too, I suspect. I've said before I am not nearly as critical a listener when it comes to movie viewing as I am for music. Earlier when talking about "Gladiator", I committed to talking about it some more, so as promised, here you go. The battle chapters, and the other, more subtle chapters, like the the wheat field at the beginning of the film, are excellently and (as best I can tell without hearing the studios masters) flawlessly rendered. Like the film or not, the soundtrack is to me, reference class. From the early battle to the conclusion, you're drawn into the Gladiator's world. I have no desire to live in that era, but it is highly entertaining!
Little else remains to be said. There are five superb channels being delivered out of this amplifier. If you've paid attention, I've put some of the buzzwords as section titles. They're also my summary of this amplifier:
Gargantuan. Behemoth. Open. Dynamic. Involving.
Balanced Audio Technology has delivered big time with this modular, multi-channel amplifier. Discussions with Steve Bednarski of BAT indicate that they are thinking along similar lines to me, and they are considering a monoblock solid state amplifier using the same modules. This would get rid of the sole complaint I have regarding its physical size and heft. Sonically, I find nothing to fault, and hope the monoblock version comes to fruition. If it does, they'll probably see me outside their door, checkbook in hand to purchase a five pack!
Kudos to Victor Khomenko for yet another superbly designed and executed product. The accolades are well deserved.
Review system in use:
Preamplifier 6-channel, multiple input review sample Preamplifer/Processor B&K Reference 30 DAC Perpetual Technologies P-1A + P-3A Front Speakers Soundline Audio SL-2 Center Channel Soundline Audio SL6-6 Surround Speakers Acoustat Spectra 22 Digital Source Onkyo DV-S939 DVD-Audio Interconnects Nordost SPM Reference and Homegrown Audio Silver Lace Speaker Cables Homegrown Audio Silver Lace, Nordost SPM Reference, Nordost Red Dawn Amplifier Stand Sound Anchors custom for VK-6200 Power Conditioning Balanced Power Transformers BP-2
Artist Recording Record Label Catalog # Hamamura Quintet Re'told / Standards No. 1 Audionet None Locatable Gordon Goodwin's
Big Phat Band
Swinging for the Fences Silverline Records 81017-9 Glen Phillips Abulum Silverline Records 86040-9 Blue Man Group Audio Virgin Records, America 7243 4 77893 9 7 Diana Krall When I Look in your Eyes Impulse IMPD-304 The Manhattan Transfer Best of Atlantic 19319-2 Gladiator Dreamworks 86386 Styx Greatest Hits A&M 31454 0387 2
- John Kotches -
© Copyright 2001 Secrets of Home Theater & High Fidelity
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