From the beginning, VTL has been all about vacuum tubes. But VTL adds its own twist to the sound of tubes, a homage of sorts to the founder’s name. VTL products are manly and refuse to concede to the solid-state crowd in terms of power and drive. As proclaimed on the VTL website, Luke and Bea believe in the trinity of power, purity, and simplicity, and they declare that “It takes muscle in the electronics for a room acoustic to approach the recreation of the live musical event.” When it comes to high-powered tubed electronics, VTL stakes out a claim as king of the hill. Many manufacturers of tubed electronics have ceded the race altogether, designing their amplifiers for high-sensitivity speakers that require only a few watts. The handful of manufacturers producing higher-powered tube amplifiers focus on monoblocks. However, that configuration requires the customer to make a more significant allowance for space, with each amplifier often demanding a place near each speaker, rather than a single amp slotted into an equipment rack tucked back toward a wall.

While some audiophiles manage to incorporate mono amplifiers in a shared living space, it is not a universally accepted domestic choice. VTL accommodates the preference for high power and space by squeezing high power into its stereo amplifiers. Its S-400 Series II Reference is rated at 300Wpc; the S-200 Signature is rated at 200Wpc. These are the two of the highest-powered stereo tube amplifiers you can buy today. Audio Research, Conrad-Johnson and VAC stereo amplifiers all top out in the 150Wpc range.

But as Mark Twain famously remarked, “It’s not the size of the dog in the fight; it’s the size of the fight in the dog.” I’ve long recognized that VTL amplifiers are exceptional. Attend any major audio show over the course of this century, whether it's the now-defunct CES or Rocky Mountain Audio Fest, or the still very much alive Munich (soon to be Vienna) High End, or the larger regional US shows, and you can be sure that some of the best sound will be in a room featuring VTL electronics.

The S-200 is not a new product, as it has been in production since late 2018. Recently, however, VTL changed vendors for some of the S-200's parts, including the manufacturer of the power transformers. With that change comes several smaller-scale revisions to accommodate the transformer change. In addition, Russia’s invasion of Ukraine has fundamentally changed the vacuum-tube market, and no manufacturer of vacuum-tube equipment sources the tubes from the same place it did six years ago.

The S-200 is a 105-pound amplifier, maxing out what most people can move around without a helper. Measuring 18 1/2" wide, 18" deep and 9" high, it fits into most racks. The eight power tubes can be 6550s, which VTL sources from Electro-Harmonix in Russia, or KT88s, which are from JJ Electronic in the Slovak Republic. In between the two sets of four power tubes are two 12AT7 input tubes and 12BH7 driver tubes, one per channel. To install or remove tubes, you remove a couple sections of the cage that fits around the unit, but as I have neither small children nor cats at risk, I left the entire cage off to enhance air circulation and achieve more efficient cooling of the tubes and the massive transformers.

The S-200 has a few more buttons and switches than most amplifiers. The back panel includes a 20-amp power inlet and the usual on/off rocker switch. The unit accepts either single-ended or balanced inputs (I used balanced only), and you must set selector switches for each channel based on your choice of single-ended or balanced cables. Around front and on top on the unit, things become more complicated. On the panel, in between the left and right banks of tubes, are two switches, one for each channel, that allow the user to adjust the output impedance of the amplifier to Low, Medium, or High and thereby change the amp's damping factor. Luke Manley suggested medium for my Wilson speakers, and when I mentioned to Peter McGrath of Wilson that I was reviewing the VTL, he also immediately suggested the Medium damping factor. The front panel also includes three more buttons. The first selects between triode and tetrode mode. The second button changes from standby, engaged by turning on the back panel rocker switch, to power on. The third button is labeled Mute, and engaging it draws down the output current to a low trickle, allowing you to leave the amplifier on and warmed up for a few hours between listening sessions, rather than shutting it down and starting warm up from scratch.

Tube amplifiers have always been a passion for some and an acquired taste for others; for still others, tubes are simply too much trouble. Like the choice between vinyl and digital, running tubes demands a lot more attention to upkeep. In addition to monitoring tube life and shelling out occasionally for new tubes, there is the laborious occasional chore of checking and adjusting the bias of individual power tubes. On top of that, tube failure in most early designs of high-powered tube amplifiers generally fried downstream parts, which required boxing up the amplifier and shipping it back to the manufacturer for repair. As amplifier size and weight has grown over the years, most have crossed the weight limit for Fedex or UPS shipment, which means loading the box onto a pallet and arranging shipment by a less convenient and more expensive freight company.

While science has yet to develop a technology that combines great amplifier sound with light weight, Luke and Bea have developed a fix for the chore of regularly checking tube bias. In October of 1999, VTL started developing an auto-bias and tube-fault sensing system -- a circuit that would automatically adjust bias to the correct level and quickly trip a fuse when a tube blows to prevent any circuitry from being affected by the blown tube. This capability was first introduced in the Siegfried amplifier, released in 2003. The system was improved by the addition of a high-current layer in the fault-sensing system with the January 2006 version of VTL's MB-450 monoblocks. Along with regular enhancements to the fault-sensing system, the innovation has trickled down to today’s S-200 amplifier circuit.

The auto-bias system controls the idle current of the output tubes, dropping out when music is being played. Each tube is adjusted individually, so the need for matched sets of tubes, so critical for most designs, is less critical and arguably unnecessary. The auto-bias circuit also lowers the idle current when the amplifier is muted, so that if you want to take a break in the middle of a listening session for a few hours, the system can safely be left on, and warmed up, without fear of a blowout while your back is turned.

used the S-200 with both 6550 and KT88 power tubes and preferred the KT88s. To my ears, the KT88s are more natural-sounding, especially with piano and orchestral music, and have a more appealing midrange tonal balance. I left those in place for the two months the amplifier remained in my system. The KT88s are a $400 option. For my money, the added $400 is more a requirement than an option. I ran balanced cables into the S-200 and agreed with the consensus that the medium damping-factor setting sounded best with my Wilson speakers. I ran in tetrode mode only. I listened to the amplifier mated with Audio Research’s Reference 6 SE preamplifier as well as VTL’s TL-6.5 Series II Signature. It worked well with both. Most amplifier/line-stage combinations are at their best when both components come from the same manufacturer, and this was no exception, so for most of my listening I stuck with the VTL TL-6.5.

As “manly” or muscular as the VTL amplifier lineup seems, I prefer to take a first pass listening to a component by evaluating how accurately it produces piano and violin, leaving a closer look at percussion and electronica for a later day. Víkingur Ólafsson's Goldberg Variations [DGG 486 4559], on clear vinyl, released a little more than a year ago, has become one of my favorite interpretations of the cycle, and it certainly is one of the best-sounding versions. I have listened to CD and LP versions on a variety of systems and heard Ólafsson’s live performance during his yearlong tour playing the cycle. It is one of those recordings that can make most any system sound better than you think it should sound. Before the introduction of compact disc, piano sound on vinyl was too often judged by its degree of wow and flutter, but this release proves that good piano sound and vinyl are not mutually exclusive. The S-200 navigated Ólafsson's piano sound perfectly. Not only was the tone spot on, with the instrument sounding like a real piano, but the attack and decay were impressive, with no added bloom or smearing.

Another LP of piano music I frequently turn to is Spielt Bottesini [Telefunken 6.42230 AS], a collection of Giovanni Bottesini compositions, with Ludwig Streicher playing double bass and Norman Shetler on piano. This 1978 piano recording dives deeply into the instrument’s lower registers and reminds us that, as good as some of today’s digital recordings are, analog still rules. Much of this recording lies within the midrange, which for me is the sweet spot for tube electronics, and the S-200 took full advantage, delivering a seductive sound without any added sweetening.

That is not to suggest that the S-200 sounds stark or fatiguing in any way. One sure test of aural fatigue is to run a new component through a gauntlet of violin recordings, and I fall back on a selection that has been on call in my home and listened to with many different amplifiers and associated equipment. A release from last year that offers a challenge to many systems is Hilary Hahn’s award-winning recording Eugene Ysaÿe: Six Sonatas for Violin op.27 [DGG 486 4177] on 45rpm LP. Unless your kit is up to the task, and your cartridge dialed in properly, Hahn’s instrument can sound a bit strident and at the same time a wee bit sluggish. Playing my favorite sonata, No.2, over and again convinced me that the S-200 delivers just the right combination of speed and density to get the timing right and demonstrate why people still love the sound of tubes, delivering a lucid account of this sometimes challenging material.

These attributes were replicated with jazz. Drummer Tony Williams’s first recording, Life Time, was reissued in the Tone Poet series [Blue Note 602448321534], and it is a perfect example of how much better some reissues can sound than the more collectable original pressings. The original Blue Note release sounds a bit pale in comparison to this reissue -- a stereo issue that neatly avoids the more common left-center-right Rudy Van Gelder staging miscue. The Tone Poet reissue reproduces a soundstage that occurs in a believable space. The drum kit sounds as well recorded as on any Williams recording -- in terms of dynamics, size and depth. My favorite cut, “2 Pieces of One,” features both Richard Davis and Gary Peacock on bass, and their lower ranges were articulate with the S-200, yet dense without the slightly lush bass sound that many systems reproduce. The S-200's extra horsepower delivered tight low bass and articulation of Sam Rivers’s tenor saxophone in its lower registers. Even for 1964, Life Time is unpredictable, with the composition going off in unexpected directions. Timing is essential to its proper reproduction, and the VTL amplifier had no trouble keeping up. A lesser amplifier might imbue a trace of sluggishness that was totally absent with the S-200.

Similarly, Voodoo [Black Saint BSR 0109], from the Sonny Clark Memorial Quartet -- John Zorn, Wayne Horvitz, Ray Drummond, and Bobby Previte -- has been one of the best sounding jazz LPs since its release in 1986. Its strengths include amazing dynamics, pinpoint soundstaging, spot-on tonal accuracy, and -- to top that all off -- an excellent musical performance. The VTL S-200/TL6.5 combination nailed these strengths. I could “see” exactly where Drummonds’ bass stands and, when it descends into the instrument's lowest registers, the S-200 is there to reproduce every nuance. Previte’s drum kit ticks all the boxes, with dynamics and cymbal shimmer to die for. Many amplifiers strain a bit keeping up with Zorn’s alto sax, but the S-200 got it exactly right without any sour edge or shrillness sometimes associated with the alto.

Is the S-200's wattage count sufficient to meet the needs of metalheads? While my normal listening habits preclude me from claiming a metal mantle, I threw some of my favorite “loud” music at the VTL to test its lease-breaking potential. The slam of a car door to open Kraftwerk’s Autobahn is as breathtaking as I have heard it sound. With the volume turned up way past what I would consider safe, the Minimoog-synthesizer bass line remained as articulate, and hence as compelling, as I could hope for. The S-200 made my lowly CD [Klingklang 5099930930028] sound so good at any level that any quest for an even better-sounding vinyl version seems pointless.

Let’s face it, Dire Straits’ Brothers In Arms [Mobile Fidelity MFSL 2-441] can make almost any system shine. Yes, it is an early digital recording, captured on a Sony 24-track digital tape machine. No one would mistake this for an analog recording, but compared to other early digital recordings, its harmonics are not threadbare, and the deep bass and dynamics almost make up for any shortcomings. I shunned the music early on, as did early critics. Over the last couple of decades, however, it has taken on an honored spot on my guilty-pleasures list, and I pull it out every time a new set of speakers or pile of electronics passes through. The S-200 made the most of a huge and open soundstage that I associate with analog recording. Drum and guitar sound spread across a vast landscape, occupying a well-defined open space, and the sound was so clean that I was too often tempted to turn up the volume to dangerous levels. Lovers of rock music will love the VTL’s well-fulfilled promise of power.

Last, but not least, was GOL’s Trance Planet [Triloka 7210-2]. This ambient/dub/electronica may not be to your musical tastes (I love it), but it never fails to shine a light on any weakness in the amplifier/speaker interface. Leaving aside the test-disc low-frequency tracks, “Angelica in Delerium” demonstrated better than any other in my collection how the lowest frequencies should be felt as well as heard. I usually judge the low bass from this disc based on how much energy I feel coming up through my chair. Falling just short of the butt thrill created by the more powerful (and far more expensive) CH Precision M1.1 amplifier, the VTL S-200 produced some of the tightest and deepest bass I have felt from this CD.

ver the years, tube electronics have become far more stable and reliable, while their performance has improved so much that they have combined the traditional tube strengths, such as liquid midrange, with attributes generally ceded to solid-state equipment, such as speed and dynamics. At the same time, the best solid-state equipment has become increasingly competitive with, and sometimes superior to, the tubed competition. The area where the two worlds collide rather than coalesce is pricing. The best solid-state options often price out at multiples of what top-drawer tube-based equipment cost.

In a nutshell, the VTL S-200 Signature produces a lot of power in a single small chassis, and it meets all the requirements for a gorgeous midrange, treble extension that reveals the last bit of shimmer in cymbals, and a bottom end that is tight and dynamic. If it has an obvious shortcoming, it is the lack of bling -- the chassis is attractive without being over the top. The technical innovations, especially the auto-bias circuit, perform beautifully, but these features operate in the background and offer few bragging rights to less self-aware audio friends. You also cannot brag about how much you spent, especially in these days of common six-figure prices. If you are working with enough space for mono amplifiers and/or are willing to and able to spend a lot more money, VTL has other amplifiers for you. But the S-200 Signature is an amplifier that will excite anyone who loves music, and in that way it will be enough for most of us.