Avantgarde • XA Power Stereo Amplifier and XA Pre Preamplifier

by Roy Gregory | May 27, 2013


The high-end-audio landscape is for the most part a predictable one. For all the high-tech claims and topological advances, there are more companies content to follow than to lead, more customers who prefer the tried and trusted to the innovative or novel. The result is a natural conservatism, the odd product that’s genuinely different standing out like a tree in a wheat field -- and enjoying about the same life expectancy. There are few truly standout companies, and few that survive long enough to create a lasting impression or leave any sort of legacy. Perhaps the most obvious exception to that rule, and not just in visual terms, is the German loudspeaker manufacturer Avantgarde Acoustics, with their spherical horn designs.

Avantgarde by name, avant-garde by nature, their iconic speakers are singular in design, hard to miss in the flesh, their often brightly colored trumpets an arresting visual metaphor for a company that seems not just unwilling but almost incapable of accepting the status quo. But there is -- indeed, always has been -- a lot more to Avantgarde than just the speakers. The surprisingly modest Model 5 integrated amplifier was followed by the ambitious single-ended solid-state Model One preamp and power amp, sonically and physically impressive designs that proved almost impossibly costly to build. At first glance, the nearly prosaic exterior of the Model 3 integrated amp looks almost normal, until you take in its subtly stylish accents. One listen was all it took to realize that it still packed enough of the Avantgarde DNA beneath the lid to surprise, even shock, more than a few listeners.

But in the end, buyers of ambitious horn-based speaker systems want more than a slim-line integrated to do the driving. And there’s the rub, the continuing conundrum that has confronted Avantgarde from day one. Their speakers place very specific demands on the partnering amplifier. With sensitivities across the range that get comfortably into three figures, low noise is a critical consideration, but so too are dynamic range and speed of response. After all, there’s no point in building those qualities into the speaker if you crush them out of the signal before it even gets that far. Then throw in the fact that the spherical horns are used in a hybrid array, underpinned by active subwoofers, and it becomes apparent that the matching amplification needs more than just dynamics and speed -- it needs authority too. It’s no accident that all Avantgarde’s amplifier designs have been solid state, nor that every time I’ve heard the speakers sounding glorious it has been with solid-state amps -- and most of the times they’ve disappointed it has been with tubes.

Finding suitable partners (in terms of both price and performance), especially amongst the low-powered triode amplifiers audiophiles instinctively seemed to reach for when presented with a high-efficiency horn system, has been an ongoing issue. Their own integrated designs were offered mainly as suitable stand-ins, able to show off the speakers’ true capabilities, but they didn’t fill the market need for a long-term solution and were never really marketed as products in their own right, existing almost as stopgap partners or demonstration tools.

Well, Avantgarde have learnt from the experience of previous forays into amplification, and things just got serious. Enter the XA Pre and XA Power, as the names suggests, a pre-power combination, but one that is, as you might expect, distinctly different.

Avantgarde amps for every man

The first and perhaps most significant thing to say about the XA products is that they are genuinely universal. No stopgaps here. These are not tied to Avantgarde speakers, and whilst they’ll obviously do a sterling job with their stablemates, they will be equally at home (and just as musically impressive) partnering with a wide range of far more conventional speaker systems. In fact, to make precisely that point, this review won’t feature a single Avantgarde speaker. Instead, I’ve used the XAs with designs as various as the Wilson Benesch Cardinal (at 90dB sensitivity), the Crystal Absolute Arabesque (at 95dB sensitivity), the KEF R900 (at 90dB sensitivity) and the Focal 807 W (at 92dB sensitivity): all box designs, none of them particular beasts to drive, but representative of many of the speakers commonly found on the market these days. If you really feel that you need more power, then the XA Power can be bridged, although this is no simple switch-flicking operation. Instead you need to invert one of the inputs using a specially built interconnect (or a Y-adapter supplied by Avantgarde) and ensure that you get the connections to the speaker terminals correct. Avantgarde can supply instructions; don’t under any circumstances try to complete the operation without them. Likewise, they can supply RCA-to-XLR input or output adapters, but purpose-built interconnects are a better solution if you need to use a single-ended source (like the majority of phono stages).

All of that should banish once and for all the idea that the Avantgarde amps will only work with Avantgarde speakers; get that right out of your head. Indeed, what makes these amps so interesting is not just what’s on the inside (which, believe me, is interesting enough) but the steps taken to ensure that they really are comfortable with more "normal" loudspeakers, meaning that people who can’t accommodate a pair of substantial hybrid horns can finally get to enjoy the genius of Avantgarde in more manageable systems.

"Genius" is not a word I use lightly, the more extreme examples of audio design more often than not being tinged with a hint or more of (creative) madness. But right from the word go Avantgarde have been founded on radical thinking and even more radical solutions. The XA electronics continue that theme, even if they do it rather less ostentatiously than the speakers. Once again, form follows function, and each aspect of the products' design can be traced directly to the guiding principles behind them. The sensitivity, dynamic range and timing integrity of the spherical horn speakers make them particularly revealing of compression, timing errors or grain in the driving signal. The Model One amplifiers adopted their radical single-ended topology, specifically to avoid cross-zero distortion, and that remains a key goal in the XA amps, along with the elimination of AC-related noise and mechanical interference caused by internally or externally generated vibration. It is the identification of these three error mechanisms that have dictated the design path taken with the Avantgarde electronics, a specifically targeted strategy aimed at maintaining signal integrity. Let’s take each type of error in turn.

Bring out the heavy roller

That’s a cricket reference for those of you who are wondering. We’ll start with the issue of microphony and mechanical resonance, simply because it has the most obvious physical effect on electronics. Just try and pick one of these products up and you’ll see exactly what I mean. They are seriously heavy -- difficult-to-lift heavy, difficult-to-place-in-a-rack-without-two-people heavy. In fact, at over 40kg, each requires two people to shift them anyway. But what makes them so heavy? One hundred fifty watts a side isn’t exactly massive output power, and when was the last time you tried to pick up a preamp that feels like it’s been nailed to the floor? The answer lies in the innovative two-piece chassis design. This consists of a massive external cast-aluminum sleeve into which slides a second, equally massive cast-aluminum monocoque tray or exoskeleton. Aluminum might be a light metal, but when there’s this much of it, even it gets heavy. More to the point, clamp the two pieces together and they become a self-damped structure of incredible rigidity. Building a chassis in this way requires multiple, extremely costly molds, one for the sleeve and one for each model’s internal layout. That makes for a massive up-front spend, but then, as designer Matthias Ruff explains, not only are Avantgarde accustomed to dealing with the high cost of molds (just consider all those trumpets), but once you have the mold, the subsequent unit cost is very low indeed, especially compared to the cost of machining a chassis this massive and intricate.

But that’s not all. The essential subassemblies of each XA Pre or Power bolt directly into pockets or lands cast within the internal chassis. That includes a complete well for the power-amp transformer and a separate housing for the preamp’s battery supply (of which more later). That makes final assembly incredibly simple and efficient, while the intimate relationship between the boards and the damped chassis makes for excellent mechanical grounding of internally generated vibration and good thermal stability. Weight aside, it’s a win-win-win solution. Besides, if you ever wanted a serious excuse for handles on an amplifier, you can rest assured that these ones aren’t for show.

Ironing out irregularities

To combat fluctuations or irregularities in the AC supply and deal with the data and RFI content that pollutes all modern domestic grids, Avantgarde have opted for a battery supply in the XA Pre. A huge block of five 2.3Ah cells is charged from a small internal supply, while the preamp is off or in standby mode. Once fully charged it is then trickle-charged to keep the batteries topped up. The battery supply itself can be bypassed if necessary via the front-panel power switch, the unit running directly from the mains. Although the sonic and musical impact of this is far from subtle, it does mean that you’ll never be left without music, while a fringe benefit is that it helps remind you what you got for all that money. Additional independent supplies are provided for the control logic and illumination functions. The result is total galvanic isolation of the critical audio circuit.

Battery power supplies have had a long and distinctly checkered history when it comes to high-end audio, but recent developments in battery performance, lifespan and reliability (driven by the massive market for mobile devices) have seen a rash of impressive new products employ the technology. Like those, the XA Pre operated faultlessly and exactly as designed throughout its time in the system. Where I would once have approached any battery-powered product with a degree of trepidation, worried by the potential sonic and operational pitfalls, now I find myself looking forward to the benefits.

Unfortunately, battery operation wasn’t an option when it came to the power amp, so instead Avantgarde resorted to multi-stage filtering, active regulation and a massive reservoir supply in order to overcome the issues with the AC input. All of the details I’ve discussed so far are covered (and illustrated) in the "Inside Avantgarde" article I wrote earlier this year, but amongst those pictures, one of the most telling is the pair of XA amplifier boards in the test jig. It really does demonstrate how much of this amp is power supply -- and how little audio circuitry! It also clearly shows the two-part chassis construction far more clearly than I can describe it.

The zero-sum game

So far so good, but everything I’ve described is simply a case of having the will to do it -- and understanding the necessity. But when it comes to eliminating cross-zero distortion, Avantgarde’s solution is genuinely innovative, ingenious and patentable. In essence, they flood the audio circuit with a DC standing current, meaning that the signal simply rides on top of that current, preventing switching of the active devices. Of course, in order to achieve this, you need to be able to flood the entire circuit, including the volume control and source selector. They have achieved this by adopting discrete resistor switching for both functions, another patentable solution, while the volume control itself acts as a shunt to ground, enabling Avantgarde to use single discrete resistors for each individual level setting. Take one look at the resistor ladder necessary to achieve this and consider the thermal dissipation necessary to support such a circuit topology and you can begin to appreciate why no one else has gone down this route. Of course, those huge, cast chassis modules help in both respects; as I said, form really does follow function. Even so, the XA Power runs distinctly warm to the touch.

Both units employ ultra-straight-line, fully complementary signal paths, with no single-ended/RCA input option. You get five line-level inputs and two pairs of outputs on the preamp, all on XLR, while the power amp has a single set of binding posts for each channel, but both XLR inputs and outputs, presumably to ease daisy-chaining a feed to the subwoofers if necessary. Given Avantgarde’s almost obsessive elimination of noise from any source, foregoing the common-mode-rejection benefits of balanced operation just wasn’t going to happen. But also in keeping with that policy, the range of facilities on offer is limited to the absolute bare minimum. You get input select/mute and volume control (the latter is also on the "light saber" remote, along with a separate mute switch). Other than that, the illumination of the volume-control dial indicates level, operational mode (battery, mains and mute) and that’s your lot -- apart from the last crucial setting, which is overall gain. This is set by holding the power switch on the XA Pre up for several seconds and toggles between low-gain and high-gain (+13dB) settings, the higher-gain option indicated by a permanently lit zero-level LED in the volume scale. That 13dB variation might seem arbitrary until you realize that it’s pretty much the sensitivity difference between a horn-based speaker and something more conventional. Even with that adjustment available, the sheer range of system sensitivities with which the XA electronics might find themselves mated means that you may well find yourself advancing the volume control well beyond industry norms. Fear not -- that’s exactly how it is supposed to work, the discrete resistor ladder of 48 1.5dB steps combined with the 13dB overall shift, allowing the XAs to deliver a ghostly quiet performance with speakers ranging anywhere from 90 to 116dB sensitivity. So when that volume control reaches three o’clock, don’t panic; just thank your lucky stars the designer of your preamp had the foresight to embrace every eventuality.

The XAs wouldn’t be Avantgarde products if they didn’t exhibit a certain flash of style, and in this case you get to select the contrasting front panel from black or silver anodized, four veneers or any of the myriad colors in which you can order the Avantgarde horns. The large and beautifully knurled volume knob is finished in black or silver accordingly. The units are undeniably big and bulky, so check rack width and height for accommodation. Ironically, given the fabulous mechanical ground offered by the interlocking cast chassis construction, the deeply ribbed fins that continue right round the body of both units make positioning couplers like Sort Kones or the LeadingEdge feet not just a bit hit and miss, but once you’ve lifted the units, they are pretty precarious. I used the larger topped Stillpoints Ultra 5s, which worked brilliantly, but be aware that your positional struggles with the XAs -- and they do take some manhandling -- don’t stop just because you’ve managed to wrestle them into a rack. Having said that, there’s no denying that once placed they do make a pretty dramatic visual statement and, even for the uninitiated, there’s no mistaking the quality of the products.

Which brings us to the question of cost: given the high initial investment required in the casework, the novel topology, the fantastic fit, finish and presentation, not to mention the sheer weight of the units and the ever-upward spiral of high-end audio prices, you might be thinking that now would be a good time to take a swift, deep breath. Well, yes and no. While the Avantgarde XAs could never be considered cheap, their sub-€10,000 Euro price tag per box looks almost like a bargain compared to most of the competition, especially when you factor in material and technological content and execution. Furthermore, weighed against a speaker range that starts at around €13,000 a pair and reaches well into six figures, they start to look like a distinctly affordable option for an all Avantgarde system. Reassuringly solid, they are expensive enough to be taken seriously, even in the context of a full Trio/Basshorn system, but not so pricey that their wallet-weakening impact will frighten the natives.

Lighting the way

The minimalist design philosophy that underpins the XA products extends to their operation. The front panels are devoid of any explanation as to what the different identical DIP switches do, and those of you inured to alphanumeric displays that inform you of everything from the identity of a source component to the total running time on the unit are going to go into cataleptic withdrawal. Instead, the XA Pre relies on color-coded lights to indicate its operational status.

For such an essentially simple device, that light show can take a little getting used to -- until you remember the old adage, "less is more." So, the left-hand switch on the front panel is the power switch. If it is illuminated with an orange glow and all the other lights are out, then the unit is effectively dormant, in charge mode. DIP it and input one will illuminate to indicate that the unit is now powered up, albeit in AC-drive mode. The volume dial will also light, a rather nice pale yellow, with the single LED indicating that the level has reverted to zero -- a sensible option given the wide range of system sensitivities with which the unit is designed to cope. DIP the power switch once more and the unit momentarily mutes -- the volume dial changes to bright blue -- while it switches to battery mode. Once the unit clicks back into play mode the power switch will no longer be illuminated, leaving the source select and volume dial as the sole status indicators. Of course, the DIP switches can flick up too. In the case of the five source-select switches, that mutes the unit (switching the dial to blue), while in the case of the power switch it powers it down to its original, dormant state -- the volume dial flashing blue to indicate that process.

Once the unit is in play mode, if you hold the power switch up for several seconds, you switch the overall gain, the high-gain mode being indicated by a permanently lit red zero-level LED on the circular volume scale/ Repeat to switch back. A single orange LED indicates the volume level. Move the control and the direction of motion is shown by a trail of LEDs, letting you know where you’ve got to, as well as where you’ve come from. That might seem like a gimmick, but again it is sensible given the sensitivity issue.

Overall, it’s a far from intuitive system, until, that is, you establish some familiarity with the process and begin to understand the logic governing it. It was certainly pretty impenetrable to start with, and initially I kept finding myself switching and listening to ensure that I’d actually selected battery mode. Fortunate then that the sonic benefits are so obvious!

The three C's: clean, crisp and clear

Think about the context in which the XA products have been designed to excel and it should come as no surprise that they are exceptionally quiet. After all, with 110dB-sensitivity speakers to drive, any residual noise (and any unnecessary attenuation and subsequent gain) is to be avoided like the plague. As well as quiet, they also need to be quick; as I suggested earlier, there’s no point in having all that potential for dynamic range built into the speaker if you choke the signal as it passes through the amp. But the really good news is that what makes the XA electronics work well with their housemates makes them truly exceptional in a more "normal" system context.

Even a brief listen to the XA combination will tell you that this amp and preamp are far from ordinary. Firstly, they are exceptionally clean and uncluttered. There’s no extraneous warmth, color, thickness or halo to their sound. They are not sweet, romantic or cuddly, and they don’t hide system failings behind a softened veil. Instead they parcel out the musical energy with a precision of scale and position that gives the very real sense that they are wringing every last ounce of energy out of the signal and placing it just so. Of course, the incredibly low noise floor helps in this regard, increasing both resolution and dynamic range, but you still have to make sense of that extra information -- get it all in the right place -- which the XAs seem to do with an effortlessly unobstructive grace.

That precision goes well beyond placement and separation. It also marks out the points where notes start -- and the points where they stop -- as well as precisely how loud they get in the process, both note to note and instrument to instrument. So, not only can you clearly hear just what one player is doing, how he leans on a note to add emphasis or accent, how he pushes through a bar to add pace or momentum -- or drops off the beat to bring a more languid quality, but you can hear how one instrument relates to another, how players play off of each other.

These relationships -- between notes and players -- are the very fabric of music. Any amplifier that fails to reproduce them will reduce the signal to mere noise. But what sets the XAs apart is the crisp clarity of their reproduction: just how clearly those facets of music-making are mapped and how clearly they are heard -- and the temporal integrity with which they arrive. The history of hi-fi is littered with super-precise, super-detailed designs that, in search of ever-greater definition, strayed into the realm of sterility. The XAs don’t make that mistake -- and here’s why.

The three T's: tactile, transparent and tracking

The ability of the XA combination to follow the energy envelope of individual notes gives those notes a real sense of shape and texture, of pluck and release, of vibrance from the bow or the purity that comes from a column of air, be that voice or woodwind. You only need to hear how much shape they give to double bass on jazz recordings; notes that are so often lumpen, ill-defined and nothing more than a meandering grumble underneath the real action suddenly have pitch and pace, and they lock to the rhythm, underpinning the music rather than dragging it back. Again, that low noise floor helps when it comes to hearing around and beneath the notes, but it also comes into play in the spatial realm, making for clearly defined positional relationships. Whether the bass player is standing or perched on a stool may not seem that critical, but it absolutely affects his angle of attack, his relationship to the strings. Where he is positioned is just as critical, the distance a key component in his relationship with the rest of the band. This is the real importance of transparency: its contribution to the temporal relationship between players, the difference that makes to arrival times. Sure, a nice, explicit soundstage adds to the sense of the original event, but it’s no use unless the musical event is just as vivid. As Einstein might have said, "It’s space and time, stupid!"

When it comes to binding all that detail and information into a meaningful whole, it’s all about responding to the demands of the signal. When the music increases in level, the electronics need to track that rise in real time, or they destroy the internal relationships between the different instruments and elements. But just as important, they must track density -- the number of instruments playing and the number that join in -- and they must also avoid any overshoot. In this case, the ability to stop is just as important as the ability to start, otherwise the excess energy that bleeds after the notes will blanket and obscure what follows, diminishing dynamic and tonal contrasts and collapsing the expressive range of the performance. The XAs’ ability to track the signal precisely is remarkable -- partly, one suspects, because any dynamic overshoot or harmonic overhang will be so ruthlessly exposed by the company’s speakers. But again, match the amps to conventional boxes and the stop/start precision they bring is like an injection of pure life into the music.

As beguiling as the sheer speed and agility of the XAs is, it does point to at least one area of compromise. All that speed, all that control come as a result of the ruthless elimination of any padding or extra weight. Comparison to the likes of Siltech’s SAGA or the Connoisseur/Berning QZ combination reveals a subtle stripping of harmonics from the tail of notes, not so much a shortening as a thinning. But it is only when you compare directly against those (vastly more expensive) combinations that the tailoring becomes apparent and, in truth, it’s far less extreme and far more carefully executed than the liberties taken by the vast majority of electronics. Instead of undermining their performance it acts to reinforce it, adding a slight highlight or emphasis to the dynamic shading, bringing a slightly more dramatic and emphatic quality to musical performances.

The three P's: presence, pattern and purpose

Because that harmonic trimming is limited to the tail of notes, there’s no shortage of immediacy or presence when playing music through the XAs. Indeed, the sheer physical substance and impact they bring to music is one their great strengths. It makes music appealing and immediately engaging, listening a rewarding and enjoyable experience. For the more cerebral works, performers and listeners there’s no shortage of finesse, but the emphatic dynamics, the boldness of the musical punctuation and the sudden, final quality of the full stops all ensure a full measure of contrast and drama. But the ability to slow the pace, become more sinuous and studied, more lyrical or affected, is just as powerful. It is easy to fasten on the detail, the note-by-note definition, poise and insight provided, but all that information adds up to a much bigger picture and the XAs are just as comfortable at the macro as the micro scale. The overall shape and patterns within the piece are wonderfully scaled and explicit, and as tempting as it is to wallow in the detail and resolution on offer, the balance between the individual and the whole is what makes music through these products so special. It makes them just as comfortable playing individual instruments or voices, situations where you can marvel at their intimacy and directness of communication, as they are with large-scale orchestral works, with their all-important structure and internal chemistry.

What is never in doubt, whether listening to the large and dramatic or the small and intimate, is the "why" that lies behind the performance. There’s nothing aimless or disjointed in the XAs’ delivery. Every note, every bar is heading in the same direction and there’s no doubting which direction that is. It gives musical performances a familiar sense of momentum, pace and purpose -- familiar, that is, from live concerts. Listening to real musicians leaves you with the unavoidable feeling that audio systems can be more than a tadge ambiguous, precisely because of that diminution so many of them impose on the musical and expressive emphasis that conductors, players and singers work so hard to create -- and which separate the really great from the merely good.

And three more P's: proof, pudding and performance

So what do all this crisp presence, immediacy and clarity of musical organization buy you in performance terms? Time to start looking at a few musical examples -- and where better than the extreme rhythmic and dynamic demands of Basie's big band? Playing "Way Out Basie" from Farmers Market Barbecue [Analogue Productions/Pablo 2310-874] provides the perfect case in point. I’ve already singled out jazz bass, but the sheer momentum in James Leary’s opening melody is toe-tappingly infectious, the perfect driver and foil for the Count’s stabbed interjections, leading inevitably to the slow build with drums and guitar and that delicious point where the piano steps from supporting comment to center stage, its abrupt dislocation the ideal step to the brass entry. It’s not just the momentum and pace, the way the track builds, the rising trends in each bar that lead higher and higher into that first big tutti, it’s the way the XAs show you the structure in the arrangement and its masterful use of the forces on hand. The perfectly measured introduction and build, the full-band entrance, the lead into the solos, each element flows naturally into the next. Big-band music is all about timing and ensemble, contrast and discipline, and the XAs bring Basie’s creation to vivid, pulsing, breathing life.

But it’s not just about fast bass and loud brass. Move on to "Beaver Junction" and that disjointed piano intro with its fractured rhythms that trip up so many systems. The XAs are so sure-footed, so tight to the signal that they map Basie’s motions with an uncannily natural ease and expressive shape that lay bare the pattern and connection between the notes. The slower tempo and more relaxed groove of the track present no challenge, the system slotting straight into the pace of the playing and the overall tempo of the piece, keeping the tuttis under control and lock-stepped with the rhythm section, despite the disparity in attack and energy levels.

This is all about music and musicians -- the way the arrangements are balanced, the way the players respond to both the discipline they demand and the space they provide. Dynamic contrasts are rarely so explicit, the relationship between band and soloist rarely so clearly or brilliantly defined. Whether it’s the dramatic impact of "Way Out. . . " or the more measured pacing and deft touches of "St. Louis Blues," there’s no sense that the amps either impose their own rhythm or impede the natural progression of the music. Temporal expression is fluid and uninhibited, whatever the tempo.

Something a little more recent? How about "Little Triggers" from Elvis Costello’s This Year’s Model [Radar RAD 3]? Product of that golden age in UK rock recording at the end of the ‘70s, this is one record that isn’t short of attitude, but on this ballad Costello steps back into a realm of bitter-sweet regret that needs careful handling if the music isn’t to overpower the sentiment. The deep, tactile bass line and cannonade of solid drums are perfectly spaced, the rhythmic hesitations and pauses echoing the underlying angst in the lyric. The musical results are almost painfully awkward and affected -- exactly as they should be, the musical power and energy harnessed to the point of the song. You might almost put it down to a heightened or exaggerated reality -- except that the XA combination draws the similar emotional power and depth of expression from a whole range of recordings, whether it’s Kleiber’s masterful control of the allegretto in Beethoven’s 7th Symphony or the riotous exuberance of the B-52s in full cry. This isn’t an additive quality that the XAs impose on the music; it’s a ripping away of expressive compression. This is the why writ large and it can come as a shock -- until you get used to it. Then there’s the point where you miss it once it’s gone. The immediacy and natural expressive range of these products is addictive -- and it is also what’s missing from too many systems.

This emphasis on rhythmic integrity and dynamic shading or impact might suggest that these are electronics for rock, pop or jazz, but the same strengths work just as effectively on classical pieces, whether it’s a case of breathing new life into the 1963 Karajan Beethoven cycle [DGG 463 088-2] or reacting to the cut and thrust, the creative intensity of the Florestan Trio (Debussy-Faure-Ravel [Hyperion SACDA67114]) or the Taneyev String Quartets [Naxos 8.572421] -- the Carpe Diem String Quartet. In each case the XAs act to bring life and vigor when required, poise and restraint when needed, pitching the emotional intensity of the performance with such a deft touch as to make it a Performance with a capital "P." Live concert recordings draw you into their atmosphere, orchestras sound better drilled and bands tighter. This is not about adding anything to the recording; it is all about releasing what is there.

A philosophical marriage of coincidence -- but what spectacular offspring

By now you’ll have gathered that I consider these electronics both very different (in terms of musical presentation) and also very special. If our systems tend to flatten musical performances, unable to match the dynamic range of real life or project its full palette of tonality, texture and layered complexity, these electronics dig way deeper than most. That in itself makes them worthy of attention, but there’s another aspect to their design that makes them additionally fascinating -- at least for me.

I’ve been working on a series of articles and reviews about system supports and infrastructure, optimizing the performance of your equipment by paying attention to the "ancillaries" that define its conditions of operation: the AC supply and distribution, electrical grounding, signal cabling, physical support and mechanical grounding. This is the approach that underpins (albeit in abbreviated form) the seminars I have given in Toronto, Denver and Edinburgh.

What makes the Avantgarde preamp and amp particularly interesting is that if the essential premise of Foundation Theory is isolating the signal (as opposed to the equipment) and eliminating external error mechanisms, these products take those principles right inside the boxes themselves. Heavy emphasis on AC quality and isolation? Check. Elimination of internally generated error mechanisms (cross-zero distortion)? Check. Attention paid to the mechanical characteristics of the chassis and draining energy out of the active components? Check. Having heard the XAs driving Avantgarde’s own speakers I know just how unforgiving their spherical horns are of not just noise but dynamic limitations or timing errors. Viewing the world through that prism, it’s hardly surprising that Avantgarde would have fastened on the same system failings that we have identified, and responded with many of the same or related solutions. But the really interesting thing is that the results are exactly the same. These amps sound like a system that has been systematically optimized to the nth degree -- and that’s before you start on their cable loom and system infrastructure. Do that job properly and the resulting performance becomes very special indeed, sounding more like people and more like life than most systems ever manage. It’s not often that two genuinely groundbreaking designs roll up almost simultaneously, but hot on the heels of the Siltech SAGA, here is the Avantgarde XA pairing. But, if the SAGA redefines what is possible, the XA Pre and Power operate firmly in the realm of what is practical -- and in some respects that makes it even more relevant.

The XAs are not perfect and certainly not indistinguishable from the live event. They are bulky, heavy and awkward to handle. They do have a character. But that character is subtle and unobtrusive and they do not impede the musical signal, in terms of dynamics or sense. What they do, and do so well, is capture the essence of that live performance, or the musicians in that recording session -- the communicative quality and directness that makes live music so captivating. The sheer clarity of performance and musical purpose they instill into conventional speaker systems (almost a touch of horn-like immediacy and presence) combines with the traditional strengths of those familiar boxes to elevate their performance significantly. I’ll be talking about the XAs in the context of Avantgarde’s own speakers when I review the Trios shortly, but for now, rest assured that these electronics are quite capable of shockingly good performance with established box-speaker designs. They are not cheap -- although in material and performance terms they are certainly a bargain -- which makes the imminent arrival of an integrated version (around 110Wpc and using the preamp’s sleeve and fascia) particularly interesting.

Avantgarde’s electronics might have been inspired by the company’s own eclectic speaker designs; they might have adopted what are unusual or unfamiliar approaches to the problems of amplifying an audio signal; they don’t even look like other amps and preamps. But these cleverly executed and innovative designs have turned a page in amplifier performance, realigning the established priorities and accepted practices to dramatic effect -- and I do mean musically dramatic! The XA electronics are involving, exciting and compelling devices, products that will project the life and energy of the musical event into your system and your room. They look different and they sound different -- both in the best of ways.

Prices: XA Power, €8800; XA Pre, €9400.
Warranty: Two years parts and labor.

Avantgarde Acoustic
Lautsprechersysteme GmbH
Nibelungenstrasse 349
D-64686 Lautertal -- Reichenbach, Germany
+49 6254 306100. www.avantgarde-acoustic.com

Associated Equipment

Analog: VPI Classic 4 turntable with JMW 12.7 tonearm, Lyra Titan i and Dorian Mono cartridges, Zu Audio Denon 103 cartridge, Nordost Blue Heaven tonearm lead and Tom Evans Audio Design The Groove+ phono stage, Nordost Odin tonearm lead and Connoisseur 4.2PLE phono stage.

Digital: Wadia S7i CD player; dCS Paganini transport, DAC and uClock; Wadax Pre 1 digital control unit. Krell Cypher CD/SACD player.

Preamps: Connoisseur 4.2, Siltech SAGA C1 Control Amplifier.

Power amps: Berning Quadrature Z monoblocks, Jeff Rowland 725 monoblocks, Siltech SAGA V1 Voltage Amplifier/SAGA P1 Current Amplifier, VTL MB-450 III monoblocks.

Speakers: Crystal Cable Absolute Arabesque, Focal 807 W Prestige, KEF R900, Wilson Benesch Cardinal.

Interconnects and speaker cables: Complete looms of Nordost Odin, Crystal Cable Absolute Dream or Ultra from AC socket to speaker terminals. Power distribution was via Quantum QRT QB8s or Crystal Cable Power Strip Diamonds, with a mix of Quantum Qx2 and Qx4 power purifiers and Qv2 AC harmonizers.

Supports: Racks are 26"-wide Stillpoints ESS (current and original versions) and LeadingEdge modular designs. These are used with equipment couplers throughout, either Stillpoints or Nordost SortKones. Cables are elevated on Ayre myrtle-wood blocks.

Acoustic treatments: As well as the broadband absorption placed behind the listening seat, I employ a combination of the LeadingEdge D Panel and Flat Panel microperforated acoustic devices. These remarkably simple yet incredibly effective acoustic panels have become absolutely indispensible when it comes to hearing what the system is actually doing.

Accessories: Essential accessories include the Feickert protractor, a USB microscope and Aesthetix cartridge demagnetizer, a precision spirit level and laser, a really long tape measure and plenty of masking tape. I also make extensive use of the Furutech anti-static and demagnetizing devices and the VPI Typhoon record-cleaning machine. The Dr Feikert PlatterSpeed app has to be the best ever case of digital aiding analog.