Riviera Audio Laboratories AFM100SE Amplifiers Review

I have already reviewed two Riviera Audio Laboratories products in the past few years, the AFM50 hybrid power amplifiers and the APL01SE preamplifier. I liked both of them very much. So when the opportunity arose to spend some time with the AFM100 Special Edition Amplifier, I did not have to be asked twice. 

AFM50 Vs AFM100-SE

If the Riviera AFM50 and AFM100- SE monoblocks are compared, the 100W is bigger and more powerful, but the ideas behind them, the basic structure, and the topology are the same. 

In an extreme synthesis: a voltage amplifier with a triode in a single-ended configuration and a power amplifier with BJT and MOS, with zero feedback and pure class A operation. These three concepts are the fundamental core of all Riviera amplifiers. 

The gain and character of the sound result from the blend of these three elements and their accurate tuning. From a mechanical standpoint, the 100W offers more space. Chiomenti did not use this space to “squeeze” a few more watts, but on the contrary to let all components work in a more “relaxed” way and apply even more elegant solutions 

The main differences between the 50 and the 100 are in the input transformer, the power stage, and the power supply starting with the input transformer, which is used for both the unbalanced and balanced inputs. 

In the 50W model, Riviera uses an extremely high-quality transformer with a Mu metal core (one of the best materials for line-level transformers). In the 100W SE, there is a top version of this transformer: its big brother, with a larger Mu metal core and even higher power output and performance.

 

In the 50W output stage, four pairs of MOSFETs are used: a very, very generous sizing, as two pairs would be more than sufficient for this application. 

In the 100W- SE Chiomenti did not simply “double” the 50W, but did even more: the final devices are not eight pairs, but ten pairs. This solution allows each device to work even more “relaxed”, as mentioned before. This type of dimensioning has high costs, but in Chiomenti experience offers significant advantages in terms of musical results. 

Last but not least: the power supply. The refinements are not simply a matter of increasing or oversizing: from this perspective, the 50W and the 100W are very similar. 

And as for the sizing… With the power transformer of the AFM100- SE other companies could easily build a 750W amplifier, but that’s not the point. 

Chiomenti sees this as a more subtle matter: a subject of quality, not quantity. 

In the power supply of the 100W- SE there is a PI filter with inductors. Compared to the equivalent resistive version, this solution not only improves the electrical performance of the filter (noise reduction) but also affects the sound quality. Although the technical results (noise) are very close, the musical result is cleaner, smoother, more elegant, and natural with this type of supply. 

Finally, the addition of distributed capacitance, as in any Riviera design. Distributed capacitance requires a little explanation.

On several occasions, Riviera has been asked by some enthusiasts why their power amplifiers do not have those huge capacitors, the size of Coke cans, usually two, that can be often found in various amplifiers. 

“Enthusiasts love them: they believe they are the sign of a great power supply, and perhaps the designers agree. A huge supply of power is a good thing when you need it. But perhaps someone has forgotten what the old saying goes: the fast horse has thin legs.” 

In electronics, a small capacitor is usually faster than a large one, for physical reasons. A large capacitor can store high energy, but it is slow. One can make a capacitor that stores high energy (large capacitance) at very high speed by simply grouping many small capacitors. Yes, at a higher cost, but the results are incomparable in Chiomenti opinion. 

There is another (big) problem with the “two Coke cans” style power supply: the distance between the capacitors where the energy is stored and the output stage where the energy is needed. 

The interconnecting cable, even if it is made of a solid copper rod, introduces parasitic elements. These further slow down the availability of energy. Distributed capacitance means that each power device has its reservoir capacitor located very close to it. The sum of many small capacitors equals or even exceeds the large energy storage provided by the large capacitors. But the many small capacitors also provide a huge reserve of impulsive energy, and this impulsive energy is available in immediate proximity to the power devices.

The sum of all these elements makes the AFM100SE’s power supply quite unconventional and may explain some of its behavior. 

In the vast repertoire of music I used in the evaluation, the Riviera Audio Labs AFM100SE amplifiers took on the role of genius loci, shaping the variety of musical landscapes and also shaping the micro and telescopic perspectives with authority. 

The pure emotional flow and outburst of “No habrá nadie en el mundo” by Buika from the album Niña de Fuego is an energetic and enchanting pure emotional thunder. 

The AFM100SE effortlessly captures this dynamic, expressing Buika’s energy and creating a palpable presence. 

Many amplifiers can make “No habrá nadie en el mundo” immutable, stripping away raw energy and momentum. Not so the Riviera Audio Labs AFM100SE, where the elements of the music come together without any embellishment.

I’ll probably never get enough of “Mondscheinsonate Round about midnight.” Ray Brown and Laurindo Almeida’s masterpiece from the album Moonlight Serenade, is another timelessly beautiful recording. 

It was most impressive how Riviera Audio Labs AFM100SE modeled the reality of “Mondscheinsonate Round about midnight” with a surprising degree of nexus points that escape the ephemeral

horizon and vertical phenomena that can seriously hinder the necessary propagation in space. 

The AFM100SE amplifiers acted as ushers, allowing the music to enter the listening room without fatigue or distraction, and allowing Brown and Laurindo Almeida to harmonize most engagingly.

Most impressively, the Riviera amplifiers produced a laser-sharp focus and an exceptional sense of space that allowed the delays and reverb to fully expand and create the needed holographic sphere that many amplifiers, regardless of price, fail to provide. 

The way the AFM100SE maintained vibrancy, weight, and sparkling power in the midrange was also remarkable. Acoustic guitar notes were instantly plucked without diminishing the sharpness of the leading edges of the notes that many Class A amps and even hybrids fail to achieve.

The liminal space and vector maps of perception with a constellation of higher order particles that AFM100SE can bestow were further confirmed with “Hullo Bolinas” from the album Swallow Tales, which brings together John Scofield, Steve Swallow, and Bill Stewart. 

This is one of the albums and especially the piece that I usually end my listening sessions with. It somehow brings order to my mind and heart. 

All of the tracks on the album are masterpieces, but “Hullo Bolinas” comes with an organicity all its own that, when everything is set right in the system, bypasses the usual sensory guards and speaks directly to the heart. 

The AFM100SE amplifiers made “Hullo Bolinas” particularly enticing and clarifying, making “visible” to the ear all the intersections, intricacies, and subtleties necessary to connect the soul, the mind, and the heart.

Another album with hidden energy and soul connection is Tanita Tikaram Ancient Heart. 

Ancient Heart moves on what I have called over the years the safe side of melancholia. Those who are also fans of the music of Sade or Bjork might recognize the silver lining. 

The music just purrs and the emotional interaction with Tikaram goes back and forth with Riviera AFM100SE monoblocks. 

The clear voice, presented with just the right weight, and size and at just the right pitch, make the AFM100SE amps top-notch, upper echelon units. There is no doubt about where they belong and what they aimed to reach. The proof is in the details, especially in “Twist in My Sobriety.” 

The Riviera Hybrid Monoblocks hit the music’s center of gravity without taking away or boosting certain frequency points or Q factors. 

They simply let the music work the way with one kind of motive force, establishing the essential ground foundations.

There is no shortcut to making the orchestral, demanding score of “I Robot” by The Alan Parsons Project from the album of the same name sound complete. 

There’s so much happening on all levels throughout this album that it’s clear from the first two minutes of the opening track whether the amp(s) will make or break it. 

The AFM100SE’s refined and highly potent sonic epicenter really unfolds on this iconic album. On a genuine high-end audio system, this is and should be a spectacle for the senses and the AFM100SE accomplishes this with top marks.

But the ultimate dynamic (sans classical orchestral music) is always “A New Jerusalem” by Karate from the album In The Fishtank 12.

While the VU meters on the Riviera AFM100SEs came close to the red zone, there was no distortion, compression, or any indication that the music was falling apart. I was amazed at what the AFM100SEs could do in terms of dynamics. They really should not, given their wattage. 

But not only that, there was no loss of harmonic richness, which can easily disappear when things get going with “A New Jerusalem.” 

The Riviera AFM100SE managed to create a perfect combination of rawness and refinement with a full grip and superb definition. “A New Jerusalem” was conveyed with a remarkable directivity that skips the rational and delivers a pure heartbeat pulse. 

No matter what music is played, one is immediately connected to the music, to the direction of the music, and most importantly, to the core of the music, from song to song and album to album. 

The Riviera Audio Labs AFM100SE responds instantly to demands, always ready to serve the deep nature of the music and allow the listeners to lose themselves in album after album without drastic discrepancies that even some more expensive amplifiers can introduce. 

The Riviera Audio Labs AFM100SE amplifiers are on par with the most iconic high-end audio products, and it’s apparent why Riviera products have already found so many happy owners among discerning music lovers and audiophiles.

An interesting coincidence/juxtaposition happened with this review. I wasn’t (due to high expectations) but then again was very surprised by Riviera Audio Labs’ flagships. 

The effect of the AFM50 amps I’ve already reviewed is still etched in my memory and left a lasting impression, so I can easily recall it in connection.

The Riviera Audio Labs AFM50 amplifiers you simply turn on, forget about and just enjoy the music. 

That’s not always the case, but this particular impression was so strong that it’s etched itself deep into my memory and is safely nested in some of those drawers that I hope will never be offloaded :). 

The Riviera Audio Labs AFM100SE monoblock power amplifiers continue the legacy of the AFM50 without changing its core and foundations but further enhance the listening experience. 

For the test, Silvio Delfino organized that the AFM100SE amplifiers were delivered together with the APL01SE preamplifier (which I have already tested here) to experience full compatibility. And the synergy was extraordinary. 

The hybrid APL01SE preamplifier has its note of natural, similar warmth, and with its gestalt, it complemented the AFM100SE amplifiers superbly, which also sounded outstandingly open for a hybrid pure Class A amplifier. driving my TIDAL Piano G2 speakers with ease, literally grabbing them by the hearts. 

In particular, the synergy with the dCS Rossini Apex DAC/Player and Rossini clock, which worked best with Rossini’s 6V output, provided a smooth current flow and never lacked bandwidth. 

I also switched to the dCS mapper 1 algorithm, which sounds a bit more solid-state with its slightly pronounced odd harmonics than mapper 3, which is more tube-like and focuses on the even harmonics. 

With this combination, the AFM100SE was at no time fatiguing. There is something fundamentally right happening under the hood of this all-Italian hybrid that connects the listener to the music. 

Luca Chiomenti has over 30 years of experience and has achieved outstanding results with the AFM100SE, which incorporates his expertise in psychoacoustics, among many other specialties.

I do not like to draw direct comparisons with other brands in my reviews, as this is a highly subjective matter and a matter of synergy, but Riviera Audio Labs amplifiers and preamplifiers operate with a unique sound foundation that I have so far only discovered in Lamm’s hybrid amplifiers, the proud creations of the sadly recently deceased Vladimir Lamm, and something he explored intensively throughout his career. 

Riviera Audio Labs’ flagship power amplifiers are characterized by a rare quality in which the spell of the music is transmitted without the message being lost in translation or rendered in a different form. This is a rare quality where the technology is subordinate to the music. 

The AFM100SE’s technology is comprehensive but never intrusive.

There is a huge difference between mediocre sounding and state-of-the-art amplifiers, and to great surprise, this difference has nothing to do with price, but a higher price these days gives you access to certain areas that use non-standard circuitry, exotic parts and materials, and so on. 

But also exotic/esoteric products do not necessarily provide the desired result. 

Sonic magic is all too often overrated and exaggerated, but Riviera Audio Labs monoblocks are in a realm of balance that is rarely achieved in the hybrid realm and is usually reserved for either ultimate tube or solid-state amplifiers. 

This is something that is perhaps not discussed enough. On the real level, where the state of the art meets the music, the amp should act as a transcendent medium with no comparison to the ordinary takes. 

In addition to spell-binding ability, the Riviera AFM100SE amplifiers feature unexpected transparency and an impressive low-end foundation that you would not expect from the stated 100 watts. 

Yes, they sound a bit more open and transparent and also have a faster attack and higher dynamics compared to the AFM50, which is logical given the huge difference of 50 watts, but that also depends on the choice of speakers. With more efficient speakers, the AFM50 Core should come very close to the AFM100SE.

The constant “troubles” with the AFM100SE were the ultimate distractions to my role as an objective reviewer because I simply became inebriated with the music. 

I just did not feel like taking my requisite listening comments and notes, I just wanted to immerse myself in the music and forget everything else because these amps did not sound warm, saturated, or with that ever-present aftertaste that is a kind of Raison d’être of many Class A or hybrid or tube amplifiers. 

Not so with the Riviera. The sound of these hybrids is pure and unaffected by the tech inside of the chassis. 

Riviera Audio Labs AFM100SE is one of those rare gems that touch my inner clock, bind my soul to music, and leave me reaching for more. No BS, no audiophile longing, just music, and more music. 

With a deep breath, the AFM100SE amplifiers can channel the soothing energy of music with a distinctive chorus and continuity of music where emotional tension is paramount. 

Delfino and Chiomenti have elevated the brand into a league of its own with these amplifiers. They were designed from the ground up to look and sound inimitably Italian. 

With their pure shapes, exclusivity, and high level of execution, they are of a different kind. 

The AFM100SE is something like the sonic equivalent of Glenturret 50 Years Old and exerts a similar appeal to the seamless ticking of the Patek Philippe Grandmaster Chime Ref. 5175.

The Riviera Audio Labs AFM100SE power amplifiers are as Italian as it gets. A musical dolce vita in a class of its own. They speak the unadulterated language of reality and sultry music sculpting. 

The AFM100SE’s powerful potency brings out the best in music and fixates an all-encompassing organicity in horizontal and vertical planes that allow the music to penetrate deep into the listening room and handle dynamic temperament at every turn. 

Yes, the AFM100SEs get very hot, warming the room, but they also warm the heart and mind. There are no half measures and Riviera Audio Labs knows this, which is why they have not compromised on engineering and sound. 

The Riviera Audio Labs AFM100SE paired with their flagship preamp is perhaps the most musical combination I have encountered in my ever-growing high-end audio journey. 

With their top-tier products, Riviera amplifiers combine the past, present, and future with masterful ingenuity, passion, and artistry created to inspire, and an industrial design that sublimely uses retro design elements but adds a touch of modernity that makes them seem timeless. 

And clearly, with AFM100SE, the tradition of high-end audio has not been truncated and tailored to a specific market segment. 

People keep telling me that I have a dream job. It is, and I am forever grateful to continue with this modus operandi. But for it to persist, you need products that do not bottle enthusiasm, and undoubtedly Riviera Audio Labs AFM100SE amplifiers are among very rare representatives of this kind. 

Because of the limitations of our senses, there is simply no other sensory pleasure that comes close to music listening, this is why listening to music transcends other so-called luxuries, and in this day and age, the real luxury is time. 

Time to spend listening to music, and time to spend engaging in that ultimate sensory delight that breathes music as it is, emotional, sensual, and with a potency of charge that can spark something extraordinary, something special, just as the svelte AFM100SE can bestow free-flowing life-like music playback. 

For what it represents musically and how deeply it immerses the listener in the true magic of music, I give these Italian hybrid monoblock power amps one of the rare Mono & Stereo Editors Choice Awards for 2022. ⧉