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Reviewer: Srajan Ebaen
Source: Zanden Audio Model 2000P/5000S; Ancient Audio Lektor Prime
Preamp/Integrated: ModWright SWL 9.0SE; Music First Audio Passive Magnetic; Bel Canto Design PRe3; Wyetech Labs Jade; Supratek Cabernet Dual; Melody HiFi I2A3; Eastern Electric M520; April Music Aura Note [on review]
Amp: 2 x Audiosector Patek SE; Yamamoto A-08S; FirstWatt F3; Bel Canto e.One S300
Headphone systems: Opera Audio Reference 2.2 Linear, Melody/Onix SP3 with KT77s or FirstWatt F1, AKG K-1000s w. hardwired Stefan AudioArt harness; Raysonic CD128, Yamamoto HA-02, audio-technica W-1000s
Digital recording: Red Wine Audio-modified Olive Symphony
Speakers: Zu Cable Definition Pro in custom lacquer with Rane PEQ55 below 40Hz; Anthony Gallo Acoustics Ref 3.1; Mark & Daniel Ruby with Omni Harmonizer; WLM Diva Monitor, Duo 12 and P/P & Bass Controls
Cables: Crystal Cable Ultra complete wire harness; Zanden Audio proprietary I²S cable, Zu Cable Varial, Gede, Libtech and Ibis; Stealth Audio Cable Indra, MetaCarbon & NanoFiber [on loan]; SilverFi interconnects; Crystal Cable Reference power cords; double cryo'd Acrolink with Furutech UK plug between wall and transformer
Stands: 2 x Grand Prix Audio Monaco Modular 4-tier
Powerline conditioning: 2 x Walker Audio Velocitor S fed from custom AudioSector 1.5KV Plitron step-down transformer with balanced power output option
Sundry accessories: GPA Formula Carbon/Kevlar shelf for transport; GPA Apex footers underneath stand, DAC and amp; Walker Audio Extreme SST on all connections; Walker Audio Vivid CD cleaner; Walker Audio Reference HDLs; Furutech RD-2 CD demagnetizer
Room size: 16' w x 21' d x 9' h in short-wall setup, with openly adjoining 15' x 35' living room
Review Component Retail: €2,895
Time Table Tripath.
Credit for discovering Tripath for high end audio consumption undoubtedly goes to Bel Canto Design under the visionary leadership of John Stronczer. That man unhesitatingly abandoned 845 power triodes in favor of digital power processing both as manufacturer and private music lover. This unprecedented move soon opened flood gates. Seven years later now, analog switching amplifiers have become a veritable staple in 2007's hifi diet. Examples thereof even appear in the catalogues of diehard tube stalwarts like ARC and Cary. However, the Tripath craze considerably waned after Bang & Olufsen's ICEpower joined the frenzy. Then Bruno Putzeys of Philips' DSL Versterkerbouwerij arrived with uCd. Then NuForce launched its aggressive campaign. Tripath diminished even more. All along, the Japanese mainstream -- including luxo brand Esoteric of late -- had begun to roll their own Class D iterations. Soon Tripath was overtaken. It was plutoed - demoted to also run as just one of many many options.


But the tides would turn again. Suddenly Tripath got an unexpected blood infusion from left field when the Target-shoppin', plastic-lovin', cheapskatin' legions discovered the minuscule Sonic Impact T-amp. This effrontery to snob appeal caused massive tremors in the audio underground. Eventually it spilled over into the mainstream. Yes, it was bare boned and raw and chintzy - but for $29.95? As it turned out, it would prove a mere harbinger of things to come. Leading to endless what ifs and inevitable copycatting, bona fide improvements soon began to appear elsewhere. The most celebrated of these T-amp clones was perhaps the Red Wine Audio Clari-T. It would eventually be completely eclipsed by its spiritual successor, the Signature 30, a wolf in sheep's clothes. This modest-looking, friendly-priced 30-watter firmly reestablished Tripath as a serious player. It also introduced sealed lead acid batteries to the core T-amp idea. This recipe did not follow the customary trend of high power ratings as pursued by most other so-called digital amps. Instead, the T gang behaved SET-ish with its focus on low double-digit figures. Soon the acronym SET began to assume a secondary meaning. It could mean single-ended transistor. Factual in some instances (think First Watt for example), in other cases it merely pointed at an aesthetic of refinement and shared tube values. This even includes a preference for more benign 8-ohm impedances and higher speaker sensitivities to partner with the lower output power.
T + (SL)A.
If T plus SLA proved such a winning and affordable recipe, it was bound to happen. Another shop would set up on this particular audio boulevard. It'd open right across the corner and offer the same dish with different garnish. From La Bella Italia, land of gelato and Monica Belluci, now comes Marco Baroncelli of newly formed Firenze Audio. But Marco's got a few ideas of his own. His contributions to the basic T-amp recipe are active crossovers, multi channel and bridging. He also clads his amps in Walnut or Cherry veneered cubes with solid wood edging. These cubes show a frontal flourish of a carved fleur-de-lis. It's what you'd expect in Louis XIV's court, embroidered on a fine table linen in a Florentine eatery or woven into another DaVincian mystery novel. Access to the crossover points, gain trim and bypass of the 4th-order networks becomes thoroughly modern meanwhile, via RS232 serial bus to PC.
Currently, three amplifier models are available - the Rosso 460B, the 460 and the 760. The first number indicates channels, four or seven. The 60 always refers to 4-ohm RMS power delivery
with 0.15% of measured total harmonic distortion and noise. At 0.01% THD+N, power drops to 20wpc into 8, double that into 4 ohms. Channels may be bridged for twice the power. The 'B' denotes battery power. The non-B versions are AC powered. For review, I was sent the battery-powered 4-channel version strapped to high-power stereo. It arrived in a trick little wooden crate ensconced in popcorn and an outer carton. Rosso travels in style.


Mere Curiosity?
The active crossover inside the Firenze amp seemed a bit of a curiosity to my way of thinking. Once you ponder how you'd actually use it, it dawns on you that the ideal scenarios -- active biamping of main speakers; a superior sub/sat split -- are quite unlikely to be the case. First off, very few commercial speakers allow you to defeat their internal crossovers. Leashing two crossovers in series instead -- one active, one passive -- completely defeats the purpose. External and hence removable crossovers à la Nola and Living Voice for example will have to be different than what's inside the Rosso. Specific crossover slopes, phase compensation and divider frequencies won't be duplicated exactly by a 3rd-party generic 4th-order filter. In the case of my Zus, the requisite low crossover point of 40Hz isn't even available. Despite the application notes for the Rosso then, active biamping of main speakers will mostly not be on the menu when reality bites. But I fired off an inquiry to the designer just in case I was being daft and overlooking the obvious. As we'll see, I was.
Secondly, most subwoofers nowadays are powered and often already by Class D. That includes their own hi-lo paths with dedicated gain and phase controls to loop a monitor speaker. In theory, lightening a monitor's burden by eliminating its bass duties is attractive. In practice, it sums all information below the crossover point to mono. Potentially more counter productive can be the veiling effects of inferior high-pass filters inserted ahead of a superior monitor's own passive crossover. Quality monitors in particular often sound rather better when run wide open. REL style, the sub is then brought in below in augmentation rather than filter mode. Would the Rosso hi-pass be more transparent than a good sub's own?


Driving the rare passive subwoofer with an external amp is nearly as unlikely an occurrence as chancing on a biwirable speaker that's got defeatable crossovers to actively biamp. However, for those who want to experiment because they live with the scenarios the Rosso addresses, the possible crossover frequencies are 70, 75, 80, 90, 120, 180, 250, 300, 400, 500, 700, 1000, 1500, 2000, 3000 and 3600Hz, with gain for the LF channels adjustable by +/-12dB in 1dB steps. Your laptop or PC will launch a screen with the requisite virtual sliders and controls and write to non-volatile memory.

For most, passive biamping will be the main application for this amp's 4-channel soul. But then there's high-power stereo. It makes the one-box Rosso into a virtual pair of RWA Signature 70s. Now that should put us at full hello. The competition is heating up.
Specs and Usage
Charging of the Rosso's twin 12V/9Ah batteries mirrors Mr. Rossi's scheme at Red Wine Audio. The power mains switch on the rear simply toggles between play and charge. Topping off the batteries after each playing session is strongly advised. SLAs neither suffer memory effects nor do they want to be fully discharged. If you limit your RMS power consumption to 5 watts, one charge is claimed to net about 15 playback hours. The included universal battery charging wall wart -- the amp's constant connection to a live wall outlet which disconnects internally when you switch to 'play' -- accepts wall voltages from 90 to 264.


The amp makes heavy use of surface-mount devices for short signal paths, with the output connectors direct-soldered to the printed circuit board to eliminate wire effects. The electronic circuits are encapsulated in a die-cast aluminum enclosure for improved shielding, with potting of key parts said to minimize mechanical vibration and to improve thermal behavior. The output filter ubiquitous for any switching amp uses dual air-core Litz inductors, visible at right in the opened sub enclosure.

Power up is controlled by a micro-processor servo to eliminate the transients and pops otherwise normal for the breed. Input impedance is 33Kohm, global gain 30dB, S/N ratio 100dB. Five-way binding posts for four channels and one pair of input RCA sockets make up connectivity. A floor-facing slot in the wooden cabinet is there to improve residual vibrations and is thought of as a quasi F hole. To replace the batteries, one merely loosens four bolts to lift up the rear panel, then one fat master bolt in the battery compartment. Using the finger holes pulls out the batteries to insert new ones.
A thorough inspection of senor Baroncelli's creation concludes that this is a very well crafted amplifier. Even though the basic idea of Class T + batteries is no longer unique, execution here is clearly no gratuitous rip off.
Not. This amp has individuality written all over it. Its 120 watts of bridged 4-ohm power per channel enter a wider arena of prospective speaker mates than the original T amp's humble 6-watt beginnings dreamed of. As the backside of my review loaner shows, the four pairs of binding posts are strapped down to two pairs via installed but removable metal jumpers.


Prior to Receipt
As the first writer to formally review Vinnie Rossi's Signature 30, I was very excited about a prospective aural rerun. To date, the Sig 30 is one of my three favorite transistor amps. The other two are the Nelson Pass FirstWatt F3 Power JFET amp and Peter Daniel's AudioSector Patek SE gainclone. You could say that I'm a slut for battery-powered Class T. If the 460B offered Sig 30 sound in four-channel or bridged double-power stereo guise, it'd be a whopper of a discovery. Purely based on website photos, I had to wait for the in-the-flesh visual appeal. Cosmetics are unique but seemed rather limited in what they would match. My wife ooh'd and aah'd the moment I lifted the amp out of its crate however. That argument got settled right quick. Italian men know women. Amore mio.

Red Wine Audio's amp is an integrated with a very high-quality passive DacT attenuator. Contrary to expectations, many will prefer it sans preamp since to outperform it stock will require a rather trick and expensive separate pre. The Italian amp has no variable master gain but counters with its bridging and biamp features. Touché on that score. If sonics were lofty, it would really be the pricing and looks that tipped the scale for prospective T-amp hunters. The weak dollar at present favors the Yanks into buying domestic. EU citizens importing American meanwhile are hit by at least 15% VAT plus shipping plus import tariffs. This often offsets any currency conversion advantages. The Firenze Audio cube could thus be more expensive on paper than the Signature 70s and still end up being more attractive for European shoppers. As it turns out, the Rosso 460B is €2,895 factory-direct (€2,695 in non-battery guise) so even there it is a virtual shoo-in with the Signature 70s at least for EU citizens.


These thoughts and observations had wrapped up my notions, preconceived and collected from the Firenze Audio website when the phone rang. The usual DHL subcontractor, a Cyprus courier service, had a package for pick up. Pointing the wheels of my li'l Mazda Demio at downtown Paphos and at 190 W x 220 D x 200 H for the actual amp (in millimeters; 7.5 x 8.6 x 7.8 in inches), I was expecting a rather petite parcel for a change. That's exactly what I got once the amp emerged from its crate. Weight was 9kg or about 20lbs, quite stout for the size but caused by the leaden batteries of course.

For testing purposes, I had two monitors in mind which occupy opposing ends of the friendly gnarly load behavior stick. At a spec'd 97dB and 8 ohm, the WLM Diva Monitor does well on 20 tube watts but its optional 'semi-active' bass EQ inserted ahead of the amp can consecutively put the screws on output devices by adding up to 12dB of boost at 30Hz to augment the monitor below its native 55Hz F3. At 82.5dB and 4 ohm, the Mark & Daniel Ruby (optionally with Omni Harmonizer, an auxiliary air motion transformer tweeter added as ambient radiator above 7kHz) plainly inhales power for breakfast. It'll milk lesser or underpowered amps dry like a black widow. Leashed to WLM's Pre/Passive Control thereafter, Ruby could really put the hurtin' on any amplifier date still left standing. This particular torture would squeeze nuts to measure testicular fortitude. T amps in general are rumored to perhaps be slightly shy in that department.

In fact, that's precisely why I had acquired the Mark & Daniel speakers after their review - to evaluate amplifier drive and control. Before we learn how that blind date developed -- or the obvious comparison to the ICEpowered Bel Canto e.One S300 -- a few words from Marco Baroncelli on his new company, his brand new amp and its features. Firenze, in case you hadn't put it together yet, is the local spelling of Florence, the famous city in Italy where Firenze Audio makes its home.


"All our products are carefully handmade and I think there will be quite a low volume production of them. I'm not interested in mass production. I would like to preserve the artisanship aspect of the items and offer something related in some way to our local traditions. Actually, it seems that women in particular like the Rosso appearance, I guess because of the resemblance to a piece of warm furniture rather than a cold amplifier rack. I hope however that this particular look will not discourage the classic audiophile accustomed to traditional amplifier enclosures.


"At this moment I'm inclined to factory-direct distribution. About the embedded crossover, I fully understand your point of view. The main reason for this technical choice, I admit, is due to another product currently under development. Here at Firenze Audio we are also designing a couple of high-efficiency two-way loudspeaker systems, trying to take full advantage of the Rosso features. We would like to offer a compact and optimized system that at the same time would preserve some degree of freedom (through the tunable crossover parameters) to allow the final user to best adapt the performance to personal taste and listening room requirements. Beside that, we think that this tunable crossover could be interesting for someone who would like to upgrade his present loudspeaker system by adding a DIY passive subwoofer."


Now the embedded PC-adjustable crossover made perfect sense. Glad I'd asked. Bundled with a pair of hi-sensitivity and deliberately passive speakers, active adjustable biamping with the facilities integrated into the amp to keep box count low is a highly desirable feature. It seems the Rosso is just the beginning of what to expect from Firenze Audio. Herr Baroncelli has a vision. A serious new player has arrived.

Just how serious was apparent the moment I began listening. For starters, I ran my Austrian Divas from their optional Pre/Passive Control box as master gain central. My customary Supratek Cabernet Dual valve preamp remained on the side lines. I wanted to take the Italian's measure without valves. It turned out that the Rosso nudged yet closer to the sound of my reference Yamamoto A-08S than the since departed Red Wine Audio Signature 30. For context, the Yamamoto with EML solid-plate 45 isn't a euphonic amp by any stretch. It's crystalline, lit up and microdynamically voluptuous and expressive. Its treble is very detailed yet elegant, its upper midrange somewhat lean but ultra transparent and very immediate. It does superb tone without thickness and excellent bass - for a SET and if used within reason.


Presumably because of its large Jensen PIO cap, the Signature 30 is warmer, softer and mellower than this tube amp. Its bass control is superior of course. And while the Yammy's noise floor is exceptionally low for a zero NFB single-ended valve device, the battery-powered Signature 30's is lower even. Especially in the bass, the T amp handles transients more obviously solid-statish. The valves have the upper hand in staging dimensionality and decay trails. These presentations between amps, though different, cover far more common ground than not. That's partly because while they don't sound exactly the same, they appeal to the same (or very similar) sensibilities.


The Rosso 460B meanwhile approaches the tubular sensibilities stated on its website differently. It portrays the elegance and textures which make transparency into more than just water. Water is fresh and unflavored but really without taste. The Rosso does transparency with taste. It's something I call texture. The Rosso does texture without warmth. That's highly relevant because in that, it's a virtual stand-in for my Emission Labs 45s. Those are very direct. They even bite when a sax wails or a Selmer guitar rips into an arpeggio. Yet they utterly lack the transistory type of edgy sharpness that gets the transient intensity right but then fails to fully bloom into the follow up.


The American T amp approaches this soft-yet-not quality of resolved tubes with warmth. That somewhat undercuts the extreme directness which the Yamamoto majors in. The Italian T amp avoids the Signature 30's warmth. It's incisive yet lacks that irritating and tiring transistor bite. And it follows up with a convincing rise in tone. It does crystalline without becoming cold or even cool. Here it departs from the Bel Canto ICEpower sound of my e.One S300. That I'd label as distinctly cool and texturally lean. The Rosso does transients like my 45s - like fast tubes, not transistors. And with superior direct-heated triodes, that does not equate to warm. This sound is not even subliminally euphonic or cottony. You'd never wish for more zing and zip as certain of the thicker and denser tubes might.


Valves still stage differently though than the Rosso. Their nonlinear behavior, in ways that are mysterious and most likely completely arbitrary, makes them capable of certain magic mushroom tricks. They place novel emphasis on notes to create deeper contrasts. This is connected to harmonic distortion as well. Because that's a function of amplitude and frequency, it's unpredictable. It's perhaps the very reason why valves can sound so startingly alive. Just like superior creative performers, they take certain liberties. Stepping out of lock with linearity, they become guilty of white lies. To the listener rather than the test bench, those lies can nonetheless seem like a greater truth.

With that statement, we enter a very muddy hole. Whenever we try to really nail that bastard of an explanation -- about why, beyond all the fancy measurements and psycho-acoustic theories, valves sound different -- we come across as esoteric, poetic and generally obtuse. And of course we always fail. We can hear the difference but damn if we can explain to satisfaction what makes it so. Needless to say, the Rosso can't do this quirky non-linear tube behavior with its spatial sculpting effects that shift the listener's emphasis. Aside from that, however, this cubic woodiness from Firenze is quite a valve clone. Its particular achievement is that it pulls this off without defaulting into warmth.


Naturally, I must qualify the choice of 'defaulting'. It all depends on where you're coming from. My favored transducers based on wideband 10-inch paper cones with very stiff pleated suspensions do tone so well and on their own that any amplification with more than a hint of warmth will quickly approach varying degrees of cloying. The fabric of the music begins to stick a bit. The space between and around the tones taffies up. You end up with consecutively more density but also opacity, more mass but less shape. Resolution and finesse suffer. For a listener with such speakers, the Rosso's tube-reminiscent sound achieved without invoking warmth -- where warmth would intend to distract from the transient-heavy behavior of transistors -- is an astonishing achievement. Now it's the speakers that produce the warmth or density effect. The amp driving them is about accuracy, openness, speed and detail but not sterility or flatness.


How my Audiosector Patek SE gain clones avoid the leanness endemic to transient-led presentations is image density. Their transient behavior, sharp and pungent, is transistor all the way. It distinctly does not sound tube like even though their fabulous image density makes them a compelling option for tube lovers. The Rosso does things differently. It approaches transients the way tubes with high resolution do. Because the Rosso doesn't tweak harmonic distortion like valves of course, it lacks the harmonically enhanced flavor of 300Bs. Premium 45s -- and 2A3s but to a somewhat lesser extent in my experience -- are faster and more crystalline. By the same token, they're far too non-euphonic for those who fancy a somewhat slower, fuzzier comfort sound (or who have zippier leaner speakers which need a counter balance).


For the latter listener, the Red Wine Audio Signature 30 would be the more suitable choice in the non-tube arena. For a modern 45-type sound hound who simply needs real-world power instead of the measly 2 watts a single-ended non-paralleled 45 is capable of -- or even the 4 watts Roger Modjeski claims he's getting from his amp -- the Firenze Audio Rosso 460B would be the closer match. 'Closer match' is tongue in cheek of course. There are very few speakers copasetic with 2 watts max (and fewer yet which are full-range). Unless you own one of 'em, you'll never know what 45s sound like in your own digs. With the Rosso, you'll come as close as I've heard. What remains dissimilar won't matter. You've never had it. Incidentally, this Rosso quality extends also into the bass. Though endowed with far better control than the valves, the overall character doesn't change colors. The bass doesn't get dry or texturally discontinuous.


Now that we've got the essential sonic signature or sound flavor of Mr. Rosso pegged, how about raw grunt? Time for Miss Ruby, the high maintenance babe in the power department. Our feisty girl looks up and down on our gentleman, bats a slow and suggestive eye lash and asks purposefully: "And just how big of a man are you, monsignor Rosso?" She wasn't the only one curious to know. The so-called T amp breed (the prior and far more powerful Bel Canto eVos excepted) has always labored under the speed limit of ultra-friendly loads. Naturally, the Ts have long since progressed beyond their original 6 watts (which were claimed to be 15 but once you inspected the distortion specs, a good linear 6 watts was about the realistic limit). Rosso bridged gives 80 or 120 watts into 4 ohms depending, again, on THD behavior. Either way, that's a lot more than 6 or 15. How far would it go?

All the way. On a first date. Still using the WLM Pre/Passive Control, anywhere between -4.5 and -6dB of unity gain netted the full-on usual review playback levels. Naturally, I didn't have much headroom left for those rare ultra-dynamic classic recording extravaganzas. But 60 watts fed from a 1V-max digital source without any preamp gain can only go so far into 82.5dB speakers pushed to happy levels. It's simple math. For my ears and SPL comfort levels, this combo rocked out just fine. It was most impressive for a number of reasons. Though small, the mid/woofer on the Ruby is capable of far higher linear excursions than intuitive. That's thanks to a patented underhung voice coil construction and oversize motor. Loaded into an exceptionally dense cabinet made of artificial compound marble, Ruby is a big girl when it comes to bad-ass bass. The requirement is simply sufficient current to damp the alignment. Otherwise the port's tuning frequency will go off like a bell whenever hit. A low amplifier output impedance is a major asset too.


Despite its similarly diminutive size, the Rosso amp delivered the necessary goods. In fact, I stacked the cards against Italian machismo yet further. I used the active analog bass EQ function of the WLM unit. In a nutshell, it creates a knee at about 150Hz and then lifts signal gain by up to 12dB at 30Hz, with a subsequent decrease below that target frequency for infrasonic protection. This function is defeatable with one flick of a switch. Dialing in a 4dB lift at 30Hz on the Rubys was very effective. Granted, it was a bit overdone for effect. Those li'l woofers were just about to jump out of their hoops. The intent of course wasn't to do pretty or completely realistic. It was discovering whether the Rosso amp would cry uncle at having to work more than double as hard in the most challenging low frequencies.


Not that I could tell. In my mind, this dirty test established that SLA battery power indeed delivered the necessary current to control challenging loads. There'll be limits of course. I would certainly recommend against certain known 3-way humdingers. Any reasonable speaker though a sensible music lovers or audiophile might want to partner with the bridged Rosso should work beautifully in the size space I'm working with [below].


An equally important aspect of my Ruby challenge was the Rosso amp's utter refusal to render obnoxious the significant HF detail this speaker is capable of. This treble performance is due to the main air-motion-transformer tweeter reaching to 1kHz plus the optionally strapped auxiliary omni AMT on top brought in solely above 7kHz. As my choices of main speakers show -- Zu and WLM -- my loyalties lie with tone. That's a more old-fashioned, less lit-up and less lean sound than currently en vogue.


This bias means that I'd err on the side of less than more treble any day of the week. In the above scenario, a passive preamp was running into a transistor amp which drove a speaker whose HF and midrange hardware nearly outweighs its lower band reproducers. As you'll appreciate, this had all the makings of potential insults. That nothing of the sort occurred was the mondo compliment to Marco Baroncelli's circuit. Recall that unlike Vinnie Rossi's amp, the 460B does not do the additive warmth trick. It behaves beautifully without needing even a minor dose of 'the fuzzies' to patch up potential textural leanness. Resolution plus textural elegance without any thickness whatsoever.


Let me put this differently. At $1,600/pr, the Mark & Daniel speaker is an absolutely fabulous device. It perfectly suits the modern hifi aesthetic and builds in completely counter-intuitive bass reach for the necessary balance. Still, I usually respect Ruby more than I'm in love. I respect the tremendous engineering that's gone into this speaker; the superb value equation; the objective performance. I know that listeners with tastes different than mine will flip. My primary motive in acquiring Ruby was as ball buster for amplifier tests. I needed something as small as possible that would store away easily when not needed but be as challenging a load as I could come up with and not cost silly money. Ruby dearest.


Of all the amps I've had in-house that can even drive her properly -- not many, mind you; I don't specialize in high-power amps -- the Firenze Audio cube has taken me the farthest beyond objective respect yet for this speaker, into subjective admiration and immersion even. That's squarely because the amp moved this non-tube speaker into Yamamoto town and had me experience the Mark & Daniel speaker from that perspective. It's a change of gestalt and feel more so than any really pronounced more or less of this and that.
That this aroma transferred so readily from the WLM to the Mark & Daniel speakers surprised me. It confirmed that the first impressions listed above did in fact cover the core traits of this amp. They will translate no matter what, especially considering that I only preceded the machine with a passive preamp to limit upstream flavoring to the CD player and cables. (Anyone familiar with the Crystal Cable Ultras already knows that flavor is not what these very neutral cables are all about). The only nit I can really pick with the Rosso machine is the tight cluster of binding posts. Banana-terminated cables won't create curses. Trying however to get two spaded cables necessary for stereo to stay put, with the hot terminals so close to the heat sinks that the necessary finger tightening (the round barrels won't accept a socket wrench) becomes an exercise in cussing... well, you'll only have to do it once. In four-channel mode, forget about spades altogether. They flat-out and categorically won't work. You might as well beat death and taxes.
Hex instead of round barrels would solve the present hand-tightening issue for 2-channel use on the outside pairs. One could then clamp down securely with a wrench and not worry about a cable turning under its own weight. Secondly, the aftern power mains switch might bother some folks. They might prefer it on the front because the back will be rather busy with tight wire bundles. It's thus less than completely convenient to get to each time you want to play the amp.

Conclusion
The Rosso 460B does all the audiophile hot-button stuff. That's a given or else I'd mentioned anything that came up short. Of all the 'single-ended transistor' amps that make up my current solid-state go-to list -- single-ended transistor not necessarily literal but suggestive simply of certain overlap with traditional SETs -- the Rosso right now is my favorite. As a diehard valve lower, it joins my small club of FirstWatt F3, AudioSector Patek SE and Red Wine Audio Signature 30 from whose members I cull each time another tube-stricken listener wants to know which solid-state amp he might like. Alas, there's one salient feature that presently makes the Rosso first among equals. It's the most powerful of this elite bunch. It'll drive the most 'normal' speakers as a result. For that reason, it must be the senior member of my private club.


Now here's a trick question. A popular saying in audio has it that it's nearly impossible to make a tube amp sound bad. By now you might be wondering. Will all battery-powered T-amps on the event horizon of the future wow reviewers no matter what? From my limited experience with two thus far, I do believe that there's some inbuilt and by now proven and somewhat predictable magic in this recipe. What it doesn't mean is that they'll all sound the same. What I expect it means is that they'll all occupy this neither-tube-nor-transistor region, in different proximities to either pole of course. Without a doubt, battery power eliminates AC harmonics and transformer hum to make for stupid-good noise floors. That's a welcome bonus for any high-efficiency player where otherwise attractive traditional tube SETs can cause problems with hum and hiss. And let's not kid ourselves - low-power valve SETs of the 2A3 or 45 kind will at best be 'good for their kind' in the bass if operated full-range. With the Firenze Audio Rosso 460B, you can apply a very similar sound in true full-range fashion and to speakers that are as far removed from 45 drive as the moons of Jupiter are from our Earth.


Who woulda thunk that the humble T-amp revival would birth real-power ultra-performance amps at a time when Class D variants other than Tripath dominate this landscape (and when Tripath is said to experience serious economic strains though stocking sufficient chips for a manufacturer is certainly no issue)? It's not a rose-tinted memory of bygones either. Bel Canto's ICEpower amps are clearly superior to their best previous eVo amps. I have one of the current Bel Canto amps in-house. If the Tripath revival was nothing more than history revisited, there'd be little point. My e.One S300 should then crush the cube from Florence. It doesn't. While I won't say the reverse is true -- crushes of any sort are for teenagers -- I will say that on my speakers, I do rather prefer the Rosso. What can say? Welcome to the jungle, Marco Baroncelli!
Manufacturer's website