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Extrapolating from the interview which you really ought to read for the whole story, the thrice factor of the Maggiore 100—on price and power over the Model 88—has a third expression. It's the most relevant. Instead of just two discrete single-ended amplifiers tied together at the outputs of each channel, there are actually six. That's a total of 12 amps for a stereo pair of chassis. Where the Model 88 connected its two amps in series, the Maggiore 100 parallels two banks of three series-connected amplifiers. Each amp runs its own discrete output transformer. Then it gets more unconventional. In this array of six OPTs there are four different kinds. Looking at the amps from the front, the left/right tube pairs close and far run transformers dissimilar from the other pair but matched for each. That's four transformers and two kinds. Meanwhile the middle pair are the free but tweaky radicals. These bottles run with asymmetrical i.e. deliberately dissimilar OPTs. That's two more kinds of transformers for a 2:1:1:2 scheme, with subtle permutations from user adjustments possible for each tube/transformer.
Brazilian samples during the exploratory audition
If that sounds kinky, it is. Eduardo de Lima's entire approach is based on many years of theoretical modeling on how distortion couples between hifi components. This relies on exploiting what he calls the wiggle room inherent in how transformers work. The so-called TimbreLock controls are bias trim pots. But offsetting them as intended redistributes the transformer loading so their magnetics strategically shift operating points. Despite the obviously greater complexity over the 30-watt precursors, these deliberate 'times-six' asymmetries with their many possible combinations are special levers. With them de Lima can—a lot more precisely he says than before—model what he believes the distortion behavior of an ideal high-power triode ought to be.

What's more, the user can adapt the combinant super tube's performance—six kinkless tetrodes manipulated to act as a single 100-watt triode biased in class A1 with 90% pentode power efficiency whilst exhibiting real triode curves—to a given system. This diminishes what de Lima calls coupling or interface distortion. Two components with x distortion each can be coupled such that the resultant distortion is lower than the sum of its parts.


To reach above/beyond the Model 88, de Lima's mathematical coefficients on distortion interaction required a greater number of variables to involve the next dimension. The core rationale for the Maggiore platform thus wasn't higher power. That's merely a lovely fringe benefit for owners of less efficient speakers who want to run these unconventional amplifiers. The core rationale was taking Audiopax's intelligent distortion management approach from the second to the third dimension. de Lima reminds us that human hearing is highly intelligent and adaptive. We are far more sensitive to change and variation than steady-state conditions. An easy example is hearing a refrigerator shut off but not being on. Change is what triggers attention.


To de Lima, the second dimension of his modeling scheme dealt with the constant system distortion. It's what the Model 88 addressed. The third dimension affects the variation of the constant distortion over amplitude and frequency. The Maggiore 100 amplifiers are first to address this higher-order distortion. It's why they needed more control levers - six TimbreLocks and kinkily shifted series-parallel transformer connections with unusual tabs and windings. The interview explains this in the designer's own words at greater length.


Relevant to reiterate is how the Brazilian prototypes of January 2011 were the first practical manifestation of this complex and purely theoretical concept. de Lima happily admits that it's not a unified neat mathematical equation or continuous theory. Rather it's a hole-ridden constantly evolving patchwork. Just so the prototypes exceeded his own predictions to a degree that—his word—shocked him. "Because things worked out too well, I had to revisit my concepts and ideas. I had to adjust certain coefficients on how distortion variations interact. Usually one must revise theories because they didn't work quite as anticipated; or not at all. Refining a concept because it worked better is very rare."


There's no direct proof that any of this distortion modeling works as imagined. But there are the actual monaural amplifiers. They were developed solely on abstracts without any subsequent circuit revisions. With the Maggiore 100 de Lima's latest ideas could finally confront reality. Very much to his surprise, sensory reality far exceeded his own expectations. That assessment was shared by six Brazilian audiophiles. They bought Maggiore 100 pairs well before the Munich show based on brief auditions of the prototypes. These sales actually financed the Swiss project. Having demoed to only 10 targeted clients, six pairs are a shocking closure ratio for very expensive new amplifiers without any finalized enclosures yet!


Any thinking reader taking the above at face value will have to expect that the Maggiore 100 exceeds the Model 88 not as a function of simply more—more power, more control, more drive—but with a quite fundamental difference. The tantalizing question is, how would this difference (that added 'dimension' of de Lima's distortion management scheme) manifest audibly? Nobody before has ever applied this line of inquiry to amplifiers with this exact control circuitry. If the core gestalt was the big mystery, an only somewhat lesser curiosity was how far beyond the built-in gestalt a user could shift/change it by working those TimbreLock controls.
Eduardo shows how proportionately tall the Maggiore 100 are especially relative to the familiar far smaller Model 88
With ten green click stops per TimbreLock (the last is red and not to be used to remain within a safe bias current range), each ring of LEDs has one yellow light to act as factory reset or recommended starting point. For each bank's positions one through three, yellow is at 10:00, 11:00 and 2:00 respectively. It's recommended to keep pairs 1 and 3 fixed. Adjust the wild cards of pair 2 in tandem. Or to get really hinky, set those different left to right. While this could be foreboding for those who need to be told what's right, it's an invitation to the more adventurous and self-reliant. Trust your ears on where to set these controls. Please yourself, in your room, with your speakers, your electronics and your music. de Lima merely guides expectations by stating that TimbreLock changes won't affect frequency response or other measurables. Instead they affect flow, subjective time and aspects like softer/sharper and relaxed/taut.
Audiopax showroom, Arpeggione flagship speaker in foreground

To touch terra firma again with basic specs, voltage gain from the 12AT7 drivers is 35 times or 23dB. Input sensitivity is 1.8V, output impedance is 2.5Ω, input impedance is 100kΩ. Each individual amplifier makes 15 watts from a triode-strapped KT88 —nearly 17 in fact—to have the sextuplet Maggiore conveniently rated at 100 RMS watts or 130 with KT120. Response is 15Hz to 80kHz (-3dB). Full-power S/N ratio is claimed to exceed 100dB. The XLR input couples to the single-ended circuitry via a small transformer to accept balanced variable sources and dual-differential preamps.

With formal Swiss production of the first 10 pairs in Q4 of 2011 completed, a pair of review loaners has been scheduled for a mid January delivery.

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