Although it seems not that long ago that Rotel announced the return of its Michi flagship brand, reviving a name first seen in the 1990s, it’s actually five years since it rolled out two integrated amps, a preamp and a choice of mono or stereo power amps, all clad in a subtle combination of matt and gloss black a long way from the raw metal and Japanese lacquer of the originals. Whereas the 1990s originals were minimalist and generally slimline components, the new Michi models adopted a purposeful look, again with minimal controls but more conventionally shaped, this combining with their less than enormous dimensions making them stand out in a high-end arena where industrial design often seems to be as much of the appeal of a product as the way it sounds.

Now there are second generation versions of three of the Michi products: the ‘entry-level’ X3 amplifier we have here, the X5 integrated and the P5 preamplifier, each of which has been revised in both analogue and digital sections, from the power supplies onward, in the quest for enhanced performance. The S5 stereo power amplifier and M8 monobloc amp continue unchanged.

At first glance, you might be forgiven for an inability to see what’s new about these ‘S2’ products: there’s just a tiny badge on the rear panel of the X3, and the front panel display briefly shows a ‘Series 2’ indication as part of the start-up procedure. But then the new generation Michi products have always been understated in this respect: there’s just the brand-name on that black fascia, with no sign of a model designation, while nowhere – not even on the rear panel – will you find any mention of parent company Rotel.

So what we have here is something of an enigma: a decidedly substantial amplifier – it’s about the size of a midrange AV receiver, at 48.5cm wide and 15cm tall, and weighs just under 29kg – with a commensurate price-tag, even if £5999 means it falls a long way short of some of the very expensive integrated amplifiers seemingly becoming fashionable in the high-end sector of the audio market. However, what lies within is what matters, and in this respect the X3 S2 is considerably more exciting than its conservative appearance might suggest.

The headline figure hints at what’s in prospect, the amplifier delivering a claimed 200W into 8ohms, rising to 350W into 4ohms, and if that means it promises plenty of headroom for the dynamics of the music you play, not to mention being able to handle tricky speaker loads, the even better news is that the Michi comfortably exceeds those figures in use, and will rival many a heavyweight preamp/power amp combination when it comes to the ability to drive hard with no signs of effort, let alone stress.

So, what’s changed from the original S3 model? Well, that amplifier used digital-to-analogue conversion from AKM, the Japanese manufacturer hit by a huge fire at its main factory a few years back, leading to supply problems and a fair few manufacturers scrabbling around for components. In the S2 version Michi used an eight-channel ‘Sabre’ ES9028PRO converter from ESS, which has established itself as the ‘go to’ supplier for many hi-fi manufacturers, but such a change isn’t just a matter of plugging in a new chip, meaning that Michi has also revised its digital input switching and master clock circuits. In addition, the USB-Type B ‘computer audio’ input – there are also three optical and three coaxial digital ins – has been upgraded, and now handles DSD audio up to DSD256/11.2MHz, while the Bluetooth section now has aptX HD compatibility.

On the analogue side – the amp has a moving magnet phono input as well as four sets of analogue inputs (three on RCAs, one on balanced XLRs) – no fewer than 96 component changes have been made, Michi explaining that ‘power supplies and audio circuitry have been re-engineered to render music with increased precision and detail with an even more immersive soundstage’.

Like most Michi (and indeed Rotel) products, the design starts with a high-quality custom-made transformer feeding the power supply section: here it’s both large and heavily shielded, and – along with the substantial bank of smoothing capacitors and side-mounted heatsinking for the output devices – dominates the view within the X3 S2’s substantial casework. The main circuitry is stacked on three layers of circuitboards to the rear of the amplifier, and as well as dual sets of speaker outputs – again custom-made for Michi, but now platinum-plated – there are preamp outputs and a pair of mono subwoofer outputs, plus a front-panel headphone socket. Also provided are Ethernet and USB-A ports, but these are for control and firmware updates respectively, and have no music-playing capability.

And while the X3 S2 looks simple (or even basic), there’s more flexibility available via the menu system: inputs can be named, and tone control settings applied for each input, and there’s also the usual bypass function for use with home cinema processors or sources with their own volume controls. You can also replace the standard display of source input and volume setting with graphical representation of the music signal, using swing-needle or bar-graph displays: I find these fly in the face of the stylish simplicity of the amp’s design, but fortunately you can also dim the display or turn it off completely.

PERFORMANCE

Describing the sound of the Michi is simple: it’s sensational. Underpinned by that impression of limitless power and bass delivered with both control and conviction, the presentation here manages to be warm and rich while bursting with detail, and the dynamic scope and speed is just as well-suited to the interplay of a small chamber ensemble as it is to the heft of a full symphony orchestra.

Driving even speakers presenting a demanding electrical load, usually those with a low nominal impedance, or one varying significantly with frequency, is no problem for this amplifier, and neither is delivering music at what the listener considers to be realistic levels, however ambitious or misguided those may be. One might be tempted to suggest that the Michi handles all this with disdainful ease, except there’s no sense of disdain here, but rather a combination of exuberance and confidence that makes listening to everything from solo piano to great choral pieces as easy as it is thrilling.

There’s nothing in any way mechanical or processed about the sound here: indeed, the Michi can sound deceptively relaxed until the music demands it unleashes more of its power, which it does instantly, deftly and in spine-tingling fashion. Add in the fact that it’s revealing enough to be used with top-notch source components, and able to drive what might seem like very ambitious speaker choices with absolute control, and it’s clear that, despite the modest face it presents to the world, this is a very special amplifier, and more than a match for many a more expensive multi-unit amplifier systems.

This feature originally appeared in the August 2024 issue of Gramophone. Never miss an issue of the world's leading classical music magazine – subscribe to Gramophone today