Hi-Fi Voice - YG Acoustics Sonja 2.3i

If in 21. century in the field of home sound reproduction something has really taken off, then it is the manufacturers who are aiming their products into the sphere of ultra high-end. So many brands with such hugely expensive equipment, cables and speakers is actually fascinating to watch. Some companies rely on extravagance, design and luxury, while others rely on extreme technologies and procedures. Rather, the American company YG Acoustics belongs to the latter group, treading the path of the extreme since 2002.

The culmination of her philosophy is the large modular model Sonja. It deserves to be called modular because the basic design consists of three modules (to which you can add a fourth external module in the highest specification, serving as a bass module) - these have different fittings to suit virtually any conceivable requirement.

You can start with the "shelf block", which eventually turns into the top block of the puzzle. There are two midrange drivers and a tweeter between them, hence the D'Appolito layout. The next step is the middle module, which you can use to create a basic column form, and there can be one bass or three midbasses. The final piece is a wide bottom module with a single bass driver, and it can be combined almost freely, which brings a quite unique opportunity to build your reference loudspeaker gradually. With each upgrade you get not only a new module, but also a new frequency switch in it, corresponding to the given configuration. It's an equally tempting system, opening the door to incremental upgrades as the company evolves its model - so if they come up with a new turnout, for example, there's no need to sell the old model and buy a new one, you simply buy an upgrade and replace the frequency turnout with one with the new specification. Well, exemplary modularity.

We had the opportunity to listen to the Sonja 2.3i version in the most up-to-date specification - the above-mentioned mid-high base module was supplemented by a middle section with one mid-bass and a lower section with one woofer.

Despite its construction from milled aerospace aluminium with fantastically precise machining (the company owns a top-of-the-range CNC milling machine, of which there are only a few in the world, and can thus afford even extreme details such as almost invisible grooving of the front wall or truly perfect fusion of individual parts), the Sonja 2.3i has an almost feminine shape - perhaps due to the narrow top part, which is followed by other parts that extend smoothly in all directions. For a Sonja 2.3i that is actually huge (179 cm in height, 43 cm in width and 72 cm in depth, all weighing a respectable 205 kg), its flowing curves with a minimum of real edges (everything is gently rounded) mean that it doesn't seem to take up too much space even in a smaller room.

All the modules of the sound box are designed to be closed, there are always speaker terminals of exemplary quality between them, but the primary ones are at the very top, very uncharacteristically high from the floor. The others function only as clutches.

The ultra-heavy cabinets sit on the floor thanks to a trio of screw-in spikes, which can also be used to select the tilt of the soundboard so that the tweeter axis points towards your ears - this helps when you're sitting relatively closer than the extra height would normally allow. The shapes of the echo chambers with a small number of parallel surfaces (due to the different arches and tilts) were modelled on software developed by the company itself. That's because founder Matthew Webster has a PhD in astrophysics from the University of Cambridge and has made a living from a young age creating bespoke computer programs for demanding calculations and modelling.

A crucial aspect of the design (and ultimately pricing) is the fact that the vast majority of the materials and components used are manufactured "in-house" - an example of the technological extremism mentioned at the beginning. It starts with selective aerospace aluminium, that ultra-precise milling machine and ends, for example, with each membrane starting as a 7 kg ingot of aluminium, which is then milled to the desired thin shape, weighing less than a gram (the waste is recycled, of course). It's an approach bordering on insanity from a normal perspective, but it allows the company to have everything exactly as the designer envisions it.

Let's begin with the tweeter. It is a woven dome with a diameter of 2.5 cm, inserted into a wide ear canal. However, there is not only fabric, but also a fine support grid, how else but milled from aircraft aluminum. This entire reinforcing skeleton is said to weigh only 30 mg and yet gives the soft canopy strength comparable to classic all-metal solutions. The magnetic system for the tweeter, called ForgeCore, is also manufactured on precision CNC machines. YG Acoustics say that it's the custom fabrication (because it's a magnet and a working chamber at the same time) that is a critical part of the design for them, and the advantage is their ability to create the entire system in three dimensions thanks to the five-axis milling machines. The result should be an above-standard low distortion of about 10 dB. This should lead to a "lighter" and more obvious presentation.

The remaining transducers use diaphragms - made of aircraft aluminum, of course - "forged" with the BilletCore technology described above (solid block milling). This leaves a cone with the required geometry and thickness of only 0.2 mm and a weight of only 30 grams. This manufacturing method also yields very low tolerances (typically said to be about +/- 0.2 dB, while tolerances for conventional transducers are between 1-2 dB). In the Sonja 2.3i you will find two 15 cm midrange drivers and two 26 cm bass drivers of this type.

The frequency switches also correspond to the ultimate class in terms of components and construction methods. They are designed according to the company's DualCoherent 2 approach, i.e. aligned in both time and frequency domains. The simulation of frequency switches is carried out on software written in-house for this purpose - the goal is to achieve a perfectly flat frequency response and almost zero relative phase deviation between the converters, i.e. (almost) achieving the theoretical ideal of +/- 5 degrees. Among other things, ViseCoil technology is applied, or encapsulating the coils in a kind of milled "holders" that eliminate vibrations - this improves control over the speaker and makes it easier to work with the amplifier.

As far as parts go, most of them come from the top of the Mundorf catalogue, but YG Acoustics use their own coils and call them ToroAir. These are toroidal coils on an air core, supposedly designed to minimize interference with surrounding components. The transition frequencies of the bands are at 65 and 1 750 Hz according to the specification.

You won't find a specific frequency response for the Sonja 2.3i, although it is vaguely indicated that it offers a tolerance of +/- 1 dB in the audible range, i.e. 20 - 20,000 Hz, which is an extremely ambitious claim, underscored by the addendum about a "realistically usable range" below 20 and above 40,000 Hz. The nominal impedance of 4 ohms admits a (not particularly critical for this class) drop to 3 ohms, and the characteristic sensitivity is 88 dB (but without details of under what conditions).

We listened to the Sonja 2.3i in the importer's virtually custom-built showroom with custom acoustics in Bratislava. What's more, the set-up was also in the ultimate league - the signal source was Roon on the Taiko Extreme server, the amplification was handled by a chain from Pilium Audio consisting of Ares, Elektra and Hercules. The digital data was fed by a Paul Pang Quad Switch, all fed through a Torus Power AVR filter. All components were mounted on Hifistay legs, crampons and accessories, interconnected by higher models from Siltech. As an alternative, an analogue setup was available with a combination of a Kuzma turntable and a DS Audio optocoupler.

In "Fine and Mellow", an original song by Billie Holiday, adapted by Eva Svobodová and Luboš Andršt Acoustic Set ("Kaleidoscope" | 2022 | Audio Video Show Prague | AVS2022), there is a subtle double bass with a beautifully authentic tension, it's fast and naturally shaped tone sounds precise, clean and "simple" at all times. Especially the strength and physicality of the impulse is perfect, the quality here is determined only by the recording. It's a bit of an understated charm of totally clean, totally tight and totally naturally dosed bass that just feels natural. A little better recording and you have the feeling of a real instrument in the room with your eyes closed, as only the best systems can. Sonja 2.3i then play with an incredible amount of self-discipline and calm.

The penetrating voice of Štefan Margita in "Dalla Sua Pace" from Mozart's "Don Giovanni" ("Kaleidoscope" | 2022 | Audio Video Show Prague | AVS2022), tuned to perfection by years of professional training, had a fantastic penetration and brilliant humanity at the same time. The system manages to convey all the nuances and subtleties impressively; there's a truly exceptional natural focus and concreteness, an unbounded energy, and a voice conveyed with utterly undimmed, unstressed, but also unstressed. The Sonja 2.3i offers absolute ease of understanding, fabulous plasticity and clarity, yet you don't even notice the speakers themselves. They are just an usher for the music and when the vocals come on, they just disappear, there is no trace of them in the music.

To say that all those bright and beautifully sounding cymbals in Deczi's "Morgan" ("Kaleidoscope" | 2022 | Audio Video Show Prague | AVS2022) were crystal clear, metallic and absolutely concrete, as if they were actually emerging from the instrument right in the room, is perhaps a waste of words. It just was, the Sonja 2.3i don't have an ounce of aggressive cuteness, just and authentic cut. So much different information that was transferred into the room was actually unbelievable - the recording is absolutely sophisticated, there are perfectly rendered reverbs, textures, everything is so technically precise that there is no trace of technicality.

From the loudspeakers, one can sense that the only real dynamic limit here is the recording itself - the "Agnus Dei" from V. J. Tomášek ("Kaleidoscope" | 2022 | Audio Video Show Prague | AVS2022) is actually a very fine recording performed by the Prague Philharmonic and the Kühn Choir, and it shows. Sonja 2.3i's speech is unrestricted, confident and mature. It's not a flashy orgy of energy, it's not fluffy drama, it's calmness, it's clarity, it's commonplace, and it's complete, unbound control. The recording is rendered completely authentically - if there is a hint of compression anywhere, you feel it, if the dynamic peak is meticulously engineered, it's familiar, and it doesn't matter if you play softly or loudly, the song's structure, legibility and dynamic gradients are still as clearly presented. Loudspeakers have a huge reserve and can withstand anything your system, your room and you can endure without losing their totally neutral character even for a moment.

Ivan Korene's guitar "Ellias" ("Kaleidoscope" | 2022 | Audio Video Show Praha | AVS2022) sounded without any overt expressiveness, the clarity is perfect and one can hardly trace any of the inherent character of the speakers as such. This is what true neutrality sounds like - not only a natural frequency balance in feeling, but also an absence of technicality and actually a certain "ordinariness" where nothing extra is felt and so you have to take a while to get used to how real the presentation is. It's actually more like watching a National Geographic documentary than a Hollywood blockbuster, if you'll allow that comparison. As for the guitar itself, it's rendered in slightly larger proportions and has everything to fit the recording, it's like being a fly on the tip of a microphone. The clarity is perfect, each string has its own perfectly articulated sound, the metal has an awesome texture and its sound connects with the warm wood of the body in the background. All that's missing is a tiny pinch to start looking for the guitar in the room.

The Sonja 2.3i are tall loudspeakers and their "space-forming" part is at the height of a standing man's ears, so despite their pronounced tilt, the image of the Virtuosi di Praga orchestra conducted by Oldřich Vlček in Vivaldi's "The Four Seasons - Concerto No. 2 in G minor" ("Kaleidoscope" | 2022 | Audio Video Show Praha | AVS2022) was perched relatively high, a bit as if you were sitting near the stage. But it doesn't matter, sensationally the sound system of the loudspeakers disappears and all that remains is a superbly sculptural image with great width and depth, where the orchestral ensemble fits without any feeling of compression. The instruments stand before you individually, quite clearly separated, there is a tremendous amount of air around them and the boundaries of each note are perfectly yet unobtrusively and cleanly played. It's also a fast paced sound in which nothing gets "bogged down", you could hardly ask for more clarity.

What YG Acoustics (or the entire chain connected to them) excel at is their ability to sound exactly like the recording, the electronics, the cable or even the pad underneath the component. Everything is audible. In the given line-up everything was tuned "without character", leaving only the nice, perhaps slightly warmer piano of Jan Hřivnáč and the fat drums of Karel Turnovský in "Romantic Piano - Foxtrot" ("Kaleidoskop" | 2022 | Audio Video Show Praha | AVS2022), a mixture of variations on well-known melodies. It was just fun, there is nothing to worry about, the music just goes, it has a great rhythm and juice (because that's what the record is). The piano is punchy, the drums perfectly realistic in their penetration and hardness.

And then came the turntable and a range of different vinyls, when the sound took on a round, soft form, acquired an obvious harmonic distortion (but with the coveted vinyl pleasantness), and you'd swear it was a different setup. This only further underscored the fact that the Sonja 2.3i's essentially "aren't" - despite their large size, their extreme construction techniques and unquestionably cutting-edge components produce a sound so precise, so clean, so responsive, that the speakers themselves approach the ideal of a non-existent character of their own. They are amazing in how much potential they hold - or rather, that their potential is actually as great as their price tag. The extreme solution in an extreme set-up offered a sound that was unexpectedly "normal", unobtrusive and as authentic as possible. It has to be said, of course, that this is not a sound for anyone who wants to be swept away by emotions and experiences in the first few seconds and then go back to their own way after half an hour. The sound of the Sonja 2.3i is like a fine wine, or a multi-course dinner at a great restaurant, or a tour of top art collections - you have to take your time, you have to tune in, and you have to take it in slowly, quietly, and only then will you appreciate that you are one step away from true perfection...

MEASUREMENT

Frequency response measurements were taken from a distance of 1 m in the axis between the tweeter and the midrange transducer in an enclosed semireverberant space with a floor area of approximately 35 square meters, with custom acoustics designed to achieve frequency and time balance.

The measurements can be considered 100% reliable in the 200 Hz band and above, in the 10 - 200 Hz band the influence of room acoustics is evident. Measurements were made using Clio Pocket software and a calibrated microphone, the loudspeakers were placed in the listening position seen in the accompanying photographs. It is measured in the reference axis at an average sound pressure level of 80 dB / 1 m.

The software doesn't measure the anechoic response, but the frequency response, taking into account the residual energy over time - so it's not a measured theoretical ideal of what the loudspeakers can do, but how the loudspeakers behaved in specific acoustic conditions.

You can see that the Sonja 2.3i easily reach some 25 Hz, and in real life they offer solid overall balance, and you can see that their energy responds to the angle of rotation, so you can tweak the amount of treble. There's plenty of bass, but not a huge excess, and basically you can see that these are truly full-range and realistically "equal" speakers.

The graph above also showed how the room speaks into the frequency response, here on the other hand are the individual components - and they work excellently. The response curve of the tweeter corresponds to how the drivers behave with the woofer when the influence of the woofer is removed. When listening from a real distance, the response is balanced.

The impedance curve doesn't dip to drastically low levels, nor does it have any extremely challenging transients. You can see the resonances on the high frequency spectrum, who knows what exactly they may be caused by. The electrical phase is also kept within easy limits, although it's not perfectly clean itself - but in the context of the category and the connected electronics, it's nothing to worry about.

SUITABLE ROOM
SMALL [<-- 20m2] [ +/- ] | MEDIUM [--> 20m2 / <-- 40m2] [ ✓] | LARGE [--> 40m2] [ ✓ ]

EUR 162 000,-
cca Kč 3 999 990,-

PROS

• uncompromising design
• the fascinating complexity of the production processes
• true reference neutrality
• possibility of modular growth from the basic model
• possibility of reasonable future upgrades
• perfectly disciplined delivery
• natural concentration
• total transparency - extremely easy to hear the influence of every part of the assembly
• dynamics without limit

RESPONSIBILITIES

• they lack any wow effect and it is necessary to carefully choose the set-up and get used to their sound
• the price is as extreme as the applied technological processes

IMPORTER: Dream Audio | www.dreamaudio.sk