January 2002

World Premiere!
Audiopax Model 88 SET Monoblocks
Review by Srajan Ebaen
Click here to e-mail reviewer

  I had met Eduardo de Lima two years ago at the 2000 Consumer Electronic Show (CES). The encounter had left lasting impressions. There was his self-effacing humility. Adorned in the slight language hesitation of a non-native speaker, it required probing and recognition to reveal a very original thinker. While endowed with the requisite engineering credentials, he prefers fluid out-of-the-box thinking to paint-by-numbers textbook design. It helps him discover unconventional solutions to very old problems. There also were the mind-bending effects of an impromptu listening session at his temporary Las Vegas apartment. This ordinary hotel room had been outfitted with a very inexpensive Audiopax system. It was patched together in ad hoc fashion with cheap wire and an old Parasound CD player. Regardless, it seduced me with a beautifully refined sound far in excess of its plain appearance or no-shock sticker price. In certain ways, this unprepossessing rig proved quite superior to most mega-buck systems at the Alexis Park and neighboring St. Tropez.

Introductions

During the summer of 2001, the audiophile rumor mill tugged on my subconscious. De Lima, thus far concentrated on affordably priced gear, was said to be working on a no-holds-barred statement amplifier. This set my thermionic instincts aglow. I contacted the designer via an old email that luckily proved still current. A few months and phone calls later, de Lima left Brazil to visit a friend in the States. He arranged for a detour to New Mexico and installed his Audiopax 3880 monoblocks in my system. Afterwards -- and because his Avantgarde Duo 2.2s were soon due to arrive for review -- I casually emailed Jim Smith, Avantgarde's US distributor, about the very inspired performance of these Brazilian amplifiers and then forgot all about it.

A few weeks later, a surprise response - Smith requested an introduction to Eduardo de Lima. A Berkeley customer of his owns Avantgarde Trios and had purchased the first pair of Audiopax 3880s sold domestically. Ever since, this doctor had urgently and repeatedly impressed upon Smith the vital need of absolutely having to hear this combination of Trios and 3880s for himself. Cognizant that this listener also owns state-of-the-art efforts from Viva, Wavelength and Art Audio -- and thus enjoys a rather rarefied perspective on top notch SET amplification -- something in Smith must have reacted. Twice in a few weeks, and without solicitation on his part, he received promptings about an amplifier that stemmed from Brazil of all places. Furthermore, at the time, virtually nobody had heard of it. Chance or providence?

As his extensive and semi-autobiographical ad campaign for Avantgarde recounts, Smith is no stranger to circumstantial intervention. In fact, he's rather sensitive to its unannounced fits of mysterious happenstance. After all, it was his first encounter with Avantgarde's horn speakers that compelled him to violate past vows, rejoin the audiophile hullabaloo once again and negotiate the exclusive distribution rights for these German hi-tech designs. Might this Audiopax hearsay turn out to be the equivalent amplifier package, a sleeping princess of sorts just waiting for her time in the sun? Might professional representation help her trade relative obscurity for the limelight of critical acclaim that could be worthy of his personal efforts? These or similar thoughts must have crossed Smith’s mind because shortly afterwards, he requested sample units and then invited de Lima to Atlanta for a personal meeting.

Consequences

It is now 2002, two years past my first encounter with Audiopax. De Lima and Jim Smith have arrived at an arrangement whereby Avantgarde-USA has become the exclusive sales and distribution agent for Audiopax in North America. In response to requests from his new associates, de Lima has incorporated certain cosmetic refinements and user features that would render his design yet more attractive.

The basic design brief of the Audiopax Model 88 calls for the recreation of the sonic aroma of micro-power 45 or 2A3 triodes via the cloning of their harmonic distortion structure with high-power pentode substitutes. It demands 845 or 211 power-triode drive and output power to control regular rather than special application speakers. It also proposes to accomplish this with run-of-the-mill tubes rather than limited-availability, expensive NOS variants.

As unlikely a combination of attributes as any feverish audiophile could conjure up, the Audiopax Model 88s deliver regardless. To briefly recap from my past column, envision two amplifier halves inside a common chassis, each half outfitted with its own pi-filter choke and output transformer but sharing dual windings filament and power transformers with the other. Each partial channel sports a 12AT7 pre-driver and KT88 power tube in a proprietary single-ended mode. That circuit is an evolution of a 1950's predecessor dubbed Super Ultra Linear. In de Lima's original iteration, it was called LM3 or Low Mu Triode with Higher Raw Efficiency Emulator and aimed at cloning a low mu triode like a 300B or 2A3. It has since evolved into Perfect Triode Simulation or PTS to signify the same concept but aiming even higher, namely cloning a dream triode that never existed – a mix of 45, 300B and 211.

The two proprietary output transformers of each monoblock are slightly dissimilar and tied together in series at the outputs to produce 30 watts of zero feedback, single-ended pentode power. De Lima refers to this scheme as ASTAT™ or Asymmetrical Series-Twin Amplifier Topology. My poetic leanings would have groped for something like Marasa since, in the ancient Voudoun religion of Brazil where these amps are from, the sacred Marasa twins, though dissimilar, represent primeval universal balance. But ASTAT in fact describes the topology to a "t". The novel tube circuit and twin-amp architecture may soon be accompanied by serious white papers if the designer finds ways to put his thoughts to paper in a fashion that protects his inventions from marauding copycats.

By The Wiggly Filaments Of The Tube G-ds!

But uniqueness or difference does not stop there yet. Two top-mounted toggle switches on each Model 88 are tied to precisely calibrated bias adjustment knobs that use circular arrays of red LEDs for visual level confirmation. Usually subtracted from the audio circuit, these LED rings should be activated only under zero signal and light up when the bias toggles connect with the KT88 power tubes. With the first left-most LED red in its 6:30 position, whatever the actual – and non-disclosed -- bias value happens to be corresponds to a read-out of 2.5V on a voltmeter's 20V scale. Each subsequent LED adds 0.1V. The tenth and final right-most LED in the 5:30 position corresponds to a 3.4V meter reading. Having two neighboring LEDs light up simultaneously locks in half-step increments of 0.05V in-between.

Without screwdriver or voltmeter, bias adjustments are easily accomplished right at the front of the amplifier. This does not require rear-panel access and thus pulling the amps off their shelves. It also obliterates the conventional insertion of a jeweler’s screwdriver into recessed slotted trim pots below the chassis surface. A voltmeter becomes redundant and allows even neophytes to feel utterly hip, comfortable and in control. There is good reason for this extreme user-friendliness. What appears like a very elegantly implemented but conventional provision for manual bias adjustment hides, in fact, a highly original feature dubbed Timbre Lock for its effects. You see, the special concept of de Lima's novel circuit architecture hinges on a fundamental understanding of the very complex distortion behavior of tubes. The minor asymmetry of the series-connected output transformers, implemented to mimic the harmonic distortion spectrum of micro-power triodes, can be fine-tuned yet further.

The bias current for the power tubes of the two amplifier halves can be set to different values. Depending on the harmonic distortion interaction of the Model 88 with a specific loudspeaker, one unique bias setting – which could be identical for both KT88s but more likely is offset, as for example 3.05 and 3.2, or LEDs 6+7 and 8 -- will lock in timbres and maximize definition. This is patently audible. After initial experimentations, it needs to be set just once, perhaps occasionally checked afterwards to account for bias drift. Beyond that, this feature should go into hibernation mode rather than become the focus of track-specific audiophile neurosis and obsession. This timbre lock is not a function of frequency response shifts. Rather, it seems to operate in the complex domain of harmonic structures and their effects on the perceived richness and rightness of instrumental tone and vocal timbres. In fact, de Lima's complex mathematical models point to a partial cancellation of harmonic distortion products that would usually arise between an amplifier and a loudspeaker. The conventional 1 + 1 = 2 arithmetic of distortion addition between amp and speaker is smartly transcended into a new form of math that adds 1 + 1 to arrive at 0.5.

Promise Delivered?

When I think Mister micro-power SET, I flash on something emasculated like the ephemeral lightness of being to suggest his quintessential calling card. It properly points to qualities like immediacy, directness and purity, but also a lack of testicular fortitude - the lightness part that is a direct function of his shortage of 1.5 to 3 inches – ahem, watts. This can sound marvelously relaxed indeed and suggest a kind of aural equanimity. However, it also tends to get congested and confused during complex passages and seems devoid of innate tension and excitement – or, as detractors would opine (and overall, I do side with them as a generic genre description) it can eventually sound boring: awfully pretty, but no attitude. What if one could have both?

To harvest the ease, naturalness, fluidity and effortlessness plus enjoy the freedom from hash, grain and electronic tension that are very real parts of the micro-power flavor – and, if one's tastes excluded music that required more slam and grit – one traditionally looked at ungainly Lowther or horn-loaded speakers. The former tend to be midrange champs with limited frequency extension in either direction, the latter seem often plagued with timbral or discontinuity problems. In the case of the Avantgardes who do not suffer either when properly set up, you’re charged a stout fee to play in those more rarefied circles of truly linear and coherent horns.

Deliverance

Enter the Audiopax Model 88s. They can give you micro-power luminosity and high-power attitude, diaphanous SET transparency and push-pull meat-on-them-bones - simultaneously. And unlike their rare flea-powered cousins, they pull this stunt with regular, not special-application speakers. One of their many secrets to this balance -- one foot solidly planted in this world, the other in transcendence -- must be the very unconventional effect of the 88s' bias current flexibility. With the speakers I had on hand (Avantgarde Duo 2.2, Vince Christian Limited E6/B12 sat-sub trio, Triangle Ventis xs, Soliloquy 6.2) adjusting the Timbre Lock acted like dialing a high-resolution lens for bull’s eye focus on a gnat's ass. Depending on how copasetic the starting-out setting was, the sound morphed from good or great to truly special in every single instance.

This unique ability to optimize the critical amplifier-loudspeaker interface -- a concept overdue in High-End audio by a few decades if you ask me -- is surely one of the major ingredients to the Model 88s’ musical prowess. If other listeners were to report equally successful results with their specific speaker loads, we might well be gazing at a novel breed of amplifier: novel not just as tube amplifiers per se – and anyone reading up further on their ASTAT™ and PTS™ circuitry will find them rather unusual – but unique as amplifiers, period. I will leave it to others more technically astute to make, measure and verify such final statements and simply let my ears report on what they heard.

(Ancillary equipment used: Marantz CDR 630 as transport, Perpetual Tech P-1A/P-3A as digital processor combo, Bel Canto Design Pre1 as remote-controlled "perfect match" pre-amplifier, Audio Magic Stealth Power Purifier for AC conditioning, Analysis Plus Oval Nine shot-gun biwire loudspeaker cable with Shakti on-lines, Audio Magic, Acoustic Zen and Clearview interconnects and assorted Walker Audio Valid Points and Shakti stones for mechanical and RF/EMI isolation, Walker Audio Ultra High Definition links for EMI/RF suppression at the speakers.)

Locking Up Timbre With Silken Handcuffs

Timb Lock is not a tone control in the conventional sense of the term. You cannot turn the treble off or goose the bass. You cannot upset the realistic tonal balance or confuse the relative prominence of one frequency range versus the other. Rather, think of this powerful feature in terms of lighting. Flash on finding the correct color value for skin tones on a TV monitor. When you get those color values right, faces look real. When you misjudge, you are either in copper tone city, pale zombie zone or another locale quite possibly novel but certainly not believable. In similar fashion, the adjustable range of the Timbre Lock effects stretches between the poles of "analytical, removed, somewhat aloof and cool" to "emotionally communicative, full of vibrancy, color and warmth". However, this scale never once vacated the area of believability. While I thus was unable to elicit excessive responses, say from "plainly un-involving" (now there’s a loaded verbal construct) to "cloyingly romantic", faint echoes of these poles do exist. Would it surprise you to learn that the latter occupies the higher bias range, as though running the tubes hotter resulted in slightly warmer sound?

The possible adjustments affect the areas of presence, image density and the aura of air or spaciousness around the performers. Most notable for my personal tastes was the ability to balance the amp/speaker interface such that the music palpably projected across the empty space between the speakers and me. The sound reached out for me rather than "remaining behind the speakers doing its thing". I am not referring to spatial forwardness, as though the images now arose in front of the speakers. Quite the contrary. I am instead pointing to another quality entirely. I can not find a better word than projection, as in casting your voice so that you’re heard. This resulted in an active and intimate communion with the music. Call it the "intensity knob". Tonal hues became richer, more varied, shades of artistic expressions deeper, as though another invisible dimension opened to add depth and profundity. Particularly with the Avantgarde Duos -- quite possibly impossible to beat in this regard -- the scope of micro-dynamic expression was noticeably stretched apart as well.

There are two elements to Timbre Lock. One is the actual bias value – say LED #2 on the ring, corresponding to 2.6 on your voltmeter if you felt like checking – the other the amount of offset between both power tubes. The latter is senior in effect to what exact value it connects with. In other words, the appropriate offset for a particular speaker – let’s call it 0.1.5V for argument’s sake – becomes the more potent aural denominator than whether you set it at LEDs 3+4 and 5 or LEDs 8 and 9+10. Shifting the anchor point for the offset does grant further performance gradations but they become subtler.

What it is not

At first glance, this innate flexibility could remind some aural bluebloods (I am referring to devotees of the Mesa Baron amplifier) of the partial triode/pentode plus adjustable feedback scheme of said amplifier. Having owned the Mesa amp and even worked for the firm during the Baron's reign, I can assure you that its feature differed from today's Audiopax Model 88 like night resembles day. The Baron’s functionality choices, related to High Fidelity as opposed to tonal grafting, were mostly rather crude by comparison. The Audiopax Timbre Lock paints with a much finer-tipped brush. This renders the feature eminently more useful if you endeavored to enhance the believability factor of this aural reality, rather than create an alternate while possibly quite fanciful facsimile thereof. Of course I cannot prove to you what gives me the confidence to make such a statement in the absence of hard measurements. Call it subjective truth then, the way you know whether you’re in love or not. And if you haven’t seen it coming yet, let me confess that I am in love with these amplifiers. Here’s why.

What it is

The Model 88s possess purity of tone in spades. However, unlike most pristine-sounding amplifiers that create that strange unpleasant pressure and subliminal ringing in your ears when things achieve realistic sound pressure levels, the Audiopax monos do not flinch at all under duress. Take Ashkelon [Piranha 1260] by Jewish/Moroccan cantor Emil Zrihan of Ashkelon’s main synagogue. Gifted with a hair-raisingly powerful voice that caused his nickname "mockingbird", it reaches into steep counter tenor territory at top-of-the-lungs intensity without breakup. His idiomatic improvisations in the traditional 'marvels' vein just beg to be heard at equivalently high playback levels. With the Audiopax amps, the physical inner-ear sensations I think of as dynamic compression and its concomitant distortion products, remained entirely absent as Zrihan upped the ante in ways that could easily peel off the wallpaper with lesser amps. The initial effect was akin to going faster and faster in a bus and, to your utter surprise, finding yourself remaining completely relaxed, forgetful of the natural reflex to grab hold of a handrail in a preemptive attempt to brace for impending disaster.

Unlike certain micro-powered amplifier prima donnas that thrive only on a carefully measured aural diet of low-calorie health foods, the Audiopax monos transfer their very real qualities into the junk food taverns of high-energy raunchy and driven music. While often not audiophile-approved, such fare constitutes the majority of material that regular music-loving folks like me listen to instead. If you do not think this is a big deal, simply envision – or better yet, recall if you have been there – the customary audiophile low-power SET demos. At subdued volumes, the sound is ephemeral, spookily three-dimensional, with virgin clarity and a kind of inner luminosity that’s particularly ravishing if you’ve never been exposed to it before. However, as soon as you proffer a hardcopy of your favorite Trip-Hop group to test the usefulness of these novel and compelling qualities, eyebrows arch and you’re quickly ushered out of the room.

The Audiopax amps instead invite such reverse flippancy. They offer freedom from electronic grit and glare even at levels befitting popular music and thereby avoid a certain texture that most amps inflict on the sound under such conditions. Neither do they add the kind of saturated tube thickness or fake voluptuousness that I have heard to a lesser extent with the 845-based Bel Canto Design SETi 40 and presently to a much larger extent hear again with the 572-based Viva Audio Devices Sintesi integrated. At $9,500, it happens to be a direct competitor. At least to these ears, it finds itself rather outclassed by the Brazilian underdogs. Where the Model 88s are lithe without being lean, fleet of foot yet perfectly capable of becoming forebodingly massive when called for, the Sintesi is denser, slower, with a top-end that’s clearly rolled-off, and a meaty kind of texture across the board that’s entirely absent in the 88s. A more even-handed comparison comes from the Art Audio PX-25. In my book, it is the best amp yet from that very remarkable stable of SETs. With the proper speakers, it’s even better than the justly famous Jota upon which I, and many reviewer colleagues, have lauded numerous highly favorable and well-deserved comments. Compared to the 88s, the PX-25 has a more muscular, brawny and kinetic demeanor, with more innate tension, as though the two-ended candle burning intensity of designer Joe Fratus was enshrined in its circuitry. Likewise, the Audiopax monos seem to reflect the temperament of its designer – very astute yet unprepossessing, compellingly at ease, confident but not needing to impress, relaxed yet keenly present.

I talked earlier about the equanimity and innate relaxation that are hallmarks of the best low-power SETs. The 88s veritably live and breathe in that temperate climate. The PX-25 roams its borders but exudes a hotter, more excitable temperament. By virtue of their monoblock status, the 88s have the edge in soundstage depth and image specificity. However, since the PX-25 is also available in monoblock livery by special order, this could be an unfair advantage.

Unlike the Viva piece, neither of these amps fits the mold of traditional tube sound. While they do things I have not heard solid-state do yet – though the Bel Canto eVo 200.4, especially in non-bridged mode, comes very close – they also do things automatically expected from superior solid-state devices: frequency domain honesty, drive and great bass. The quantity of bass is surprisingly similar, yet the quality remains distinctly different. Instead of the explosive attack and sharp leading edges, great single-ended tube bass is more organic, as though more cohesively enfolded in the remainder of the spectrum rather than standing out in slammatronic techno color. While devotees of the latter will find fault with the Model 88s or PX-25, subscribers to outdated thermionic preconceptions would be shocked to hear how truly full-range these modern tube designs have become.

Possibly by virtue of its greater power reserves, bass control of the Audiopax in the nether regions was superior to the formidable PX-25, even though in an output transformer shoot-out, the Art Audio amp would pummel the Brazilian amps to a bloody pulp – its trannies are about four times larger. The Audiopax transformers are yet another very unique ingredient to de Lima's recipe. While apparently devilishly complex, they are Lilliputian by design specifically to enhance bass performance – something to do with obtaining an optimized value of primary inductance that happens to be much lower than the traditional formulae of "the best primary inductance is the highest one" religion. How this counter-intuitive, text-book-defying approach really operates is above my head. More importantly, my ears clearly validate that it works wit aplomb, with plenty of trance/ambient albums acting as exhausted but convinced expert witnesses.

In the end, the comparison between PX-25 and Model 88s led to a surprising conclusion: the 6wpc Art Audio PX-25 is a genuine while high-gain micro-power amp but sonically does not quite act it. The Audiopax Model 88s are micro-power impostors that epitomize all their unique sonic strengths while controlling regular speakers that for all its swashbuckling glory even the PX-25 champ could not wake up. The 88s extend the peculiar micro power SET bouquet to embrace all kinds of music, at all kinds of output levels, and do not limit you to specialist fare. Put in automotive terms, the Audiopax monos are quad-valved, turbo-charged hotrods with the drive and moxy to overtake all those wheezing single-cylinder antiques that even at redline could not move a regular loudspeaker. And instead of gulping up high-octane, overpriced NOS tubes, they go on regular unleaded, standard KT88s and 12AT7s.

Audiopax

The name is deftly fitting. It could mean making peace with your audio worries. It could signify experiencing musical peace during your listening sessions. Both would seem equally apt. I could go on endlessly about further illustrative examples to underscore the uncommon marriage of pellucid refinement and sovereign guts they represent, a meeting between Diana Krall and The Gladiator. Instead, I will leave this to other reviewers. I will conclude with a brief quote from a late December Avantgarde-USA round email that announced the forthcoming collaboration with Audiopax I have chronicled in my intro:

"…Eduardo sent me a sample [amplifier] to evaluate. I had to admire his quiet confidence. I’d told him about our reference amplifiers – Art Audio Jota and PX-25; BAT VK 75 SE; various Carys; Lamm ML2, Pass Aleph 3; 47 Labs Gaincard; TRON 300B; Viva Aurora & Sintesi; Wavelength Triton & Mercury AG, and more. Undaunted at this list of superb reference amplifiers, he sent the amplifier anyway. And that is when I got in trouble…"

Even looking beyond sincere representational commitments, anyone familiar with the vagaries of today's economy and its impact on High-End audio sales will realize that an import/distribution firm like Avantgarde-USA, concentrated on the upscale market as it is, would have to be exceedingly selective about adding a non-speaker product to their present offering. The fact that these partners felt compelled to do so with a brand virtually unknown in the US at this time -- though it has been established in Brazil for a good four years – and were diligent enough to compare their contender against the cream of the crop before the coup speaks volumes. It suggests, regardless of personal taste issues, that the Audiopax Model 88s play in the major leagues and howl with the big dogs. This is certainly my personal conclusion and as such simply based on good old-fashioned subjective listening evaluations. That they’re highly unconventional is beyond a doubt. That they could indeed be harbingers of a new type of amplifiers seems equally predetermined.

The Bottom Line

Because my review pair was a late pre-production sample, I consider today's article less a formal review and more a sneak peek introduction of a very exciting new product. If my experience and exposure level are to be trusted for a semi-cloudy crystal ball prediction, the Audiopax Model 88s should turn out to be one of those once-in-a-blue-moon component occurrences that reviewers live for to discover. I certainly hope that other magazines and writers will take an interest in these designs to afford them further inspection, comparisons and technical measurements to pave the ground for qualified consumer interest. Without a doubt, they deserve it with a vengeance. Because of it, I’m planning on a much briefer follow-up report – pinned then to concrete music samples rather than today’s historical and technical items -- once full production commences.

Some brief comments on the ratings: Not being final production samples, fit and finish will be further improved, as will very minor residual transformer hum via vacuum impregnation. Electrical noise, as evidenced by the 103dB+ sensitive Avantgardes, was phenomenally low - with the mechanical vibration entirely suppressed, the self noise rating will be even higher, damn impressive for any amp and much more so for a tube design. Soundstaging commenced behind the plane of the speaker baffles; hence soundstage extension into the room amounted to zero. Regarding value for money - based purely on performance and what these amplifiers compete against, an even higher rating would be applicable. However, $10,000 for any audio component is hardly in the realm of child's play, hence a somewhat more sober value.

Manufacture's Reply

Dear Editor,

Srajan Ebaen is very perceptive when he suggests that it was a significant step to go forward with this project. Though there were many, these were the main issues, any one of which was big enough to make us want to think long and hard:

TOP TEN REASONS WHY WE SHOULDN'T DO THE AUDIOPAX AMPLIFIER

AUDIOPAX is an unknown product/brand in the US, which makes the introduction and subsequent marketing/support effort much more difficult.

Hey, when's the last time you heard ANY high-end amp from Brazil?

Single ended amps are still seen by the audio establishment (the Audio Police) as being flaky and weird. Certainly not a "serious amplifier" (which they define as at least 50-100 watts, probably push-pull, and very likely transistorized).

Who needs still another wimpy single ended amp?

And for sure, why go against the grain with a single-ended pentode amp (not even the hallowed triode we all know & love)? 

Listen, this amp has dinky (not cheap, just relatively small) output transformers. Who's gonna believe that apparently everyone else is wrong and we’re right when we say that we get way better bass partially BECAUSE we don't use big transformers?

How're we gonna explain why this amp has two complete circuits in each monoblock?

What could possibly make the potential market for this amp any larger than the market for the others?

We already had excellent liaisons/relationships with some of the very manufacturers with whom we'll now be competing. Was it worth it to complicate those friendships for the (relatively) small potential income from a single (relatively) expensive amp?

While the Avantgardes have been 99.5% free of service requirements, electronics have typically required more support. Were we prepared to provide the resources for customer service for a tube amp - after all, aren't tubes unreliable?

TOP THREE REASONS WHY WE DID IT ANYWAY

One listen to these babies and you're toast. Many of the other amps we've heard are great. But this one’s playing in a new league it started, all by itself. That's why we're gonna make it easy for people to try out a pair at home. Everyone who listens to it knows just what we mean.

Eduardo de Lima. His unmatched flat-out quest for at least three separate areas of design achievement did the trick: Although he has more innovations in this one amplifier that in any four other amps of which we’re aware, it's all about elegant, out-of-the-box solutions that are simple, "why didn't I think of that" concepts.

His commitment to a profoundly moving musical experience is beyond any we've seen, and certainly beyond any we've experienced emotionally from electronics.

Maybe it harks back to the days when he designed telecommunications hardware & software (which simply cannot break if it’s to succeed in the market). Eduardo designs with an eye to ultra conservative tube operation and very high durability and reliability. We've field tested a bunch of his amps, subjecting them to abuse that would cause other high-end amps to self destruct. We never did damage a Model Eighty Eight. In fact, we simply never had a failure! This technology and the resulting musical high that it produces simply had to be introduced to serious music lovers. SOMEBODY had to step up. It's so good, so far beyond anything we ever heard (or heard of), that we really had little choice.

Anyway, we took another look at the TOP 10 REASONS WHY WE SHOULDN'T... and tore up the list. Hey, after introducing horns to audiophiles who’d accepted the "common knowledge" that all horns were "colored," this project looked kind of familiar...

All the best,

Jim Smith
President, Avantgarde-USA

Specifications

Type: Single-ended, zero global feedback pentode-based tube monoblock amplifiers 

Novel aspects: 

· Proprietary PTS™ Perfect Triode Simulator output stage

· ASTAT™ Asymmetrical Series-Twin Amplifier Topology uses two independent amplifier halves per monoblock whose dual output transformers are series connected for 30 watts of RMS output power 

· MPS™ matched power supply design combines speed and ultra-low noise 

· Timbre Lock™ manual bias current adjustments allow a range of user-selectable settings that optimize the amp/speaker interface and maximize timbre and definition - top-mounted toggle switches activate two circular LED rings that connect to the power tubes and light up to confirm Timbre Lock settings - rotary knobs change settings and replace volt meter or screw driver

Tube complement: cryogenically* treated KT88 power tubes (2) and 12AT7 pre-driver tubes (2) per monoblock

*(Audiopax acknowledges the audible efficacy of cryogenic tube treatments but admits to not having good scientific explanations. The curious reader is referred to my interview with Jennifer White-Wolf Crock who is a specialist in that arena and performs deep-immersion Cryogenic treatments in her own lab.)

Chassis: consists of central chrome-plated bridge with wooden or lacquered side cheeks and plinth, chromed handles and stand-offs and gold-plated front-mounted name decal.

Rear panel: circuit breaker acts as fuse-less power switch and activates a relay to prevent in-rush current - Cardas rhodium-plated 5-way binding posts and RCA input jack

Dimensions: 13.5" (including tubes) x 9" x 14.5" (HxWxD)

Weight: 42 lbs each

Retail: $9,997 per pair introductory price

Company Information

Distributed in North America by Avantgarde-USA
6445 Calamar Drive
Cumming, GA 30040

Voice: (770) 777-2095
Fax: (770) 777-2108
E-mail: HornGuys@aol.com 
Website: www.avantgarde-usa.com