In mid-2017 Hi-Fi+took the opportunity to audition and review YG Acoustics’ flagship Sonja XV (for eXtreme Version) four-tower loudspeaker system and found it to be a world-class and state-of-the-art product in every way. At the same time, though, the speaker’s sheer size and daunting $265,900 price tag meant that only a select few with rooms big enough and wallets deep enough would ever be likely to enjoy the Sonja XV in action. But what of those passionate audiophiles who live in (somewhat) smaller spaces and who would prefer to keep their loudspeaker investments in the five-figure range? People, meet the Sonja 2.2!
The three-way, four-driver Sonja 2.2 is, like almost all YG Acoustics models, a modular loudspeaker. At its top, the Sonja 2.2 features a midrange-tweeter-midrange module nearly identical to the one used in the Sonja XV, while down below is a sealed, acoustic suspension woofer module. Both the upper and lower modules use cabinet enclosures milled from solid aircraft aluminium and whose panels are fastened together using what YG describes as aircraft-type “vibration-free pressurised assembly” techniques. Internally, the cabinets use YG’s proprietary FocusedElimination™ anti-resonance technology, which is said to keep “mechanical losses lower than any competing speaker, by combining the minimised turbulence of a sealed design with the low friction otherwise associated with enclosure-free concepts.”
The mid-bass drivers and woofer employed in the 2.2 feature proprietary YG BilletCore™ diaphragms, which are machined out of thick cylinders of aircraft-grade aluminium and are treated to jet-black anodised finishes. For those curious about such things, let me mention that YG chooses to go with machined diaphragms—as opposed to stamped metal, ceramic, or exotic composite diaphragms—because machined diaphragms allow more precise dimensional tolerances, allow complicated 3D shapes that enhance rigidity and freedom from unwanted resonance, impose less stress on the aluminium materials used, and, most importantly, exhibit greater long-term structural integrity after hours and years of use.
The single woofer used in the 2.2 is the same type as the four woofers used in the Sonja XV, while the mid-bass drivers are essentially identical to those used in the XV, but with the notable difference that the 2.2’s mid-bass drivers are run down a 65Hz crossover point, whereas the same drivers in the XV operate down to a 337Hz crossover point and then transition to a trio of dedicated lower mid-bass drivers.
Importantly, the Sonja 2.2 is treated to the exact same BilletDome™/ForgeCore™ tweeter used in the Sonja XV, which is quite frankly the finest piston-type tweeter I have yet heard in any loudspeaker. The tweeter is a hybrid design that combines a fabric dome (chosen for its desirable damping properties and smooth roll-off characteristics) with a precision-machined and ultra-low-mass (30 milligram) aluminium support frame (which adds tremendous rigidity and strength, while giving the tweeter better high-frequency extension than either a fabric or metal dome tweeter would enjoy). The term ForgeCore™ in turn refers to the fact various elements of the tweeter’s motor structure have been CNC‑cut to receive special 3D geometries that are said to minimise distortion while imparting “a sense of ease to the sound”. It is impossible to overstate the importance of this special tweeter to the Sonja 2.2’s overall sound; the tweeter effortlessly reproduces extremely low-level high-frequency transient and textural details, in the process enabling the speaker to create soundstages of exceptional breadth, depth, purity, and precision.
The Sonja 2.2 crossover network is fashioned from exceptionally high quality parts and circuit boards whose extra-thick traces are milled—not photo-etched—in place. Among the special parts used are YG’s custom-made ToroAir™ air-core inductors and, for the low-frequency portion of the crossover, the massive and highly vibration-resistant ViseCoil™ bass inductors first created for the Sonja XV. Relative to even the finest off-the-shelf bass inductors, the ViseCoil™ inductors are said to reduce residual loss by 24% and to improve linearity by a stonking 60%, in the process enabling “better control over the woofers” and fostering greater overall bass definition and impact. If you are sceptical that specialised inductors can make a significant difference in a speaker’s overall sound, just try listening to a pair of Sonja 1.2’s built before the advent of the ViseCoil™ inductors vs. a pair of Sonja 2.2’s; the qualitative improvements wrought in the 2.2’s low-end are readily apparent.
Finally, the exact crossover network topology used in the Sonja 2.2 is, as are all YG Acoustics’ crossover networks, shaped by the firm’s proprietary DualCoherent™ design software, which is the brainchild of company founder and Senior VP – Chief Engineering Officer, Yoav Geva. While there are many good loudspeaker-oriented CAD/CAM software packages available today, Geva’s DualCoherent™ design software enjoys the singular ability simultaneously to co-optimise both frequency response and relative phase response (typically competing software systems can optimise one or the other, but not both at once). Though I’m not an engineer, I can’t help but think that Geva’s DualCoherent™ software is a big part of the ‘special sauce’ that helps give YG’s loudspeakers their characteristically quick, clear, tightly-focused, and neutrally balanced sound.
In a nutshell, the Sonja 2.2 represents a careful re-make of the firm’s predecessor 1.2 model, but one that adds the two distinguishing technical features that set the mighty Sonja XV apart; namely, the aforementioned BilletDome™ tweeter and a crossover network equipped with ViseCoil™ low-frequency inductors. Since both the inductors and—especially—the tweeters are time and labour-intensive to make, there is a cost increase between the Sonja 1.2 and the 2.2, from $72,800/pair to $76,800/pair. Once listeners have heard the sonic improvements ushered in by the 2.2’s design, though, I think most would agree the price increase is money well spent.
Importantly, YG Acoustics has deliberately not left Sonja 1.2 owners behind, so that for a fee they may have their speakers upgraded to 2.2-status (it’s great to see a company like YG stand behind its customers and its earlier designs in this way). Similarly, it is possible for Sonja 2.2 owners to upgrade their speakers to have them become two-woofer, three-module Sonja 2.3 models should the need arise. However, as readers will learn in this review, the Sonja 2.2 has a distinctive sonic appeal all its own (more on this in a moment).
For my listening tests I was invited to audition the Sonja 2.2’s in the studio/mid-size listening room of GTT Audio/Video in Long Valley, New Jersey, USA (GTT’s listening rooms enjoy a reputation for superb sound quality so that many manufacturers prefer to hold product roll-out events at the GTT facility rather than at their own factories). The test system comprised a suite of Audionet amplification and analogue and digital source components, a Kronos turntable and tone arm fitted with an Airtight phono cartridge, and a complete loom of Kubala-Sosna Elation-series cables.