YG Acoustics Sonja 1.2 Loudspeaker

YG Acoustics entered the specialty audio scene at the upper end of the full-range, high-performance speaker market right from its beginnings. It did not build a line of mid-priced products to establish marketshare and then “design up” from there. YG applies a fundamental design principle to all its loudspeakers—they must simultaneously have near-zero relative phase and flat frequency response. Apparently, optimizing both is fairly difficult; phase or frequency performance is usually favored at the expense of the other. In order to realize this goal, some key engineering elements must work together at very precise levels, and thus YG’s nearly obsessive attention to high-quality materials and manufacturing exactness means that its products remain expensive—$24,300 to $106,800. YG would rather stay true to its ethos than compromise in order to offer a more market-accessible product range.

YG was founded in 2002 in Israel, but really didn’t begin to develop its manufacturing potential until it opened its current factory in 2004 near Denver, Colorado. It is the creation of Yoav Geva, a relatively young man—as far the principals of high-end companies go—still in his mid/late thirties. Geva applied some of his experience in digital signal processing to an algorithm in the analog domain, which, in turn, formed the foundation to his proprietary phase/frequency-optimized crossover design. YG calls the technology “DualCoherent,” and it is, as mentioned, the raison d’être of the company. Based on extensive modeling of his concept, Geva knew he needed to build speaker cabinets from a more rigid and stable material than was possible with wood, or he would not be able to execute the very close interplay among the various parameters involved in his design.

Accordingly, YG machines a great deal of its products’ contents from high-quality aluminum billet. Machined aluminum provides several advantages as a cabinet and cone membrane material: good strength-to-weight ratio, relatively high resistance to environmental factors such as corrosion and high temperature (helpful when machining friction heats the stock), the ability to be machined into a wide variety of custom shapes to very precise tolerances. Aluminum also has relatively good resonance damping characteristics when properly constructed. YG uses mostly aircraft-grade 6061-T651 billet. I’ve visited the YG factory and have to say that the CNC machines (computer numeric control) are truly impressive. Each “BilletCore” radially and concentrically ribbed driver cone takes at least four hours to mill on a five-axis CNC milling and turning machine from Germany called the Gildemeister CTX Beta 1250 TC. Many parts are machined to within 0.0008″ (20 micron) tolerances. (For more information about YG, please see the company’s profile in The Absolute Sound’s Illustrated History of High-End Audio, Volume One: Loudspeakers.)

Product Description
The two-module Sonja 1.2 is priced at $72,800 per pair and is available as a fully passive system (as reviewed); alternately, its bass module can be equipped with a powered, adjustable on-board amplifier and crossover to form a semi-active system for the same price. Consumers may also opt for the flagship Sonja 1.3, which adds yet another woofer module (also passive or powered to match the existing 1.2 bass module), bringing the price to $106,800 per pair. The three-module configuration increases the height from 51″ to 70″, and the weight from 296 pounds to 506, making the more imposing 1.3 a good fit for listeners with a large—or otherwise bass-attenuating—listening room and/or for those craving truly effortless and impactful bass. I have heard both the 1.2 and 1.3 in a few different installations. The 1.2 will be plenty of speaker for most home listening applications, but the 1.3 does deliver better performance overall; the additional bass module seems to add even more ease and clarity to the entire presentation, not just in the low end. Both the 1.2 and 1.3 are usually purchased in their fully passive versions, just as YG recommends.

The upper module houses two 6″ aluminum “BilletCore” mid/woofers, and one 1″ waveguide-mounted “ForgeCore” silk dome tweeter in a D’Appolito arrangement (a tweeter flanked by midrange drivers above and below the tweeter). The waveguide apparently aids in making the dispersion pattern of the tweeter closer to that of the mid/woofers. (The crossover point between the bass module and upper module is 65Hz and is, presumably, why YG refers to the mid-sized drivers as mid/woofers rather than midrange drivers.) The two-way, 124-pound upper module (known as Sonja 1.1) can be purchased separately as a stand-mounted monitor for $38,800; the bass module can be added later to form the three-way Sonja 1.2 system. The bass module has one “BilletCore” 10.25″ driver, which is positioned fairly low in its gently curved, tapered cabinet. YG found this location maximized consistent bass performance through the driver’s proximity to the floor and also minimized cabinet resonances. Each module has an inner cabinet that is mounted inside an outer cabinet. They are not merely double-layered as such. Each box has its own joints and can function as a stand-alone enclosure. This extra manufacturing complexity must surely add significantly to the overall cost, but YG says its makes each complete cabinet system much more rigid and resonance-free than either an equivalently thick, single-layered or a shared-joint, double-layered cabinet. Sonja is the only model in the line with this cabinet-in-cabinet construction. The 1.2 has three pairs of custom binding posts for single-wiring, bi-wiring, bi-amping, tri-wiring, or tri-amping.

YG has executed a stunning design in the Sonja, and in order to deliver the kind of performance and quality involved, the company has gone to very costly lengths to bring it to market. As far as super-speakers go—the cost of which can rise well over $150,000 per pair—the Sonja 1.2 is priced relatively competitively. Taking into account high-end audio pricing in general and given my sense of what goes into making the Sonja specifically, I believe the 1.2’s pricing is well within industry norms. For whatever it is worth, YG has invested over $1m in German and custom-built CNC machines, and sources all of its materials and parts from either North American or European suppliers (like top-level Mundorf capacitors and resistors). YG manufactures the vast majority of its parts itself including fasteners, driver components, binding posts, and even proprietary toroidal inductors. The amount of in-house manufacturing is very high and accords YG an astonishing level of control and precision, all of which add to the cost of production.

Listening
As already mentioned, the Sonja 1.2 is simply stunning—dynamic range, frequency extension, tonal purity, transparency, soundstaging and imaging…all stunning, sometimes goose-bump-inducing, and often involuntary grin-raising as it calmly goes about its musical business. The Sonja 1.2 does not have an easily identifiable dominant sonic character such as “lively” or “silky,” nor does it have an apparent bottom-up or top-down tonal balance. Rather, the 1.2 seems to simply convey the content of the recordings it is tasked to play back—and the characteristics of the gear with which it is partnered, of course—without adding much apparent character of its own. Its dynamic envelope is very wide, and yet it is also able to track delicate dynamic shifts. It is, in fact, capable of planar-like detail retrieval, purity of timbre, and overall refinement. It also conjures—recording permitting—a very large soundscape, and populates it with solid, naturally focused individual images without exaggeration or etch. So, at the end of the day, you have a remarkably transparent, dynamically deft, and musically expressive loudspeaker with the ability to recreate an expansive and focused soundstage. As you can tell already, in pretty much any regard, the Sonja 1.2 did not disappoint.

One of the main differences I heard when the 1.2 replaced the YG Kipod II (Issue 236) was the effortless way the 1.2 breathed yet more lifelike dynamic snap and immediacy into nearly every recording I played. The Sonja set an entirely new performance level in my system in terms of its overall dynamic envelope and lack of apparent distortion in explosive bass-heavy passages. The bass drum strikes at the end of Rabaud’s Dances from Marouf, Cobbler of Cairo on the DSD download of Exotic Dances from the Opera [Oue, Minnesota, RR] just sailed by with much of the percussive thrill of a live orchestral crescendo and no signs of strain. The 1.2 also conveys small dynamic shadings beautifully. It can sound like a fantastic mini-monitor, or a fine planar speaker, in its ability to communicate subtle differences in dynamic emphasis, the sort of shadings musicians seem to naturally use to create drama and lyricism in their performances. Take the song by Anouar Brahem called “L’aube” on Le Voyage De Sahar [ECM], for example, in which Brahem plays his oud with such delicate touches that it evokes the mood of a calm, morning bath. The full extent of the peaceful, focused beauty of the song doesn’t come through on less dynamically adroit speakers.

Other standout qualities are the 1.2’s marvelously extended frequency range and tonal accuracy. YG says, “Usable output extends from below 20Hz to above 40kHz.” I believe the phrase “usable output” refers to how the speaker’s bass interacts with room boundaries in a typical domestic setting to yield a lower frequency response than would otherwise be the case in an anechoic test chamber. Putting aside how this may compare to more traditional +/-3dB specifications, I can say the 1.2’s bass extension certainly sounds convincingly full-range in my setup, and in every other system in which I have heard it. The low notes on Joseph Bonnet’s “Variations de Concert,” played by organist Jan Kraybill [Organ Polychrome—The French School, RR], sounded deep-reaching, full, and well defined in pitch, without room-induced overhang or bloat. The synthesizer bass notes on the Aphex Twin’s Syro cut called “s950tx16wasr10 (earth portal mix),” were so deep and powerful, they bordered on frightening, such were the grip and speed with which the lowest notes launched into the room.

The Sonja does not add a heightened sense of “bass presence” as many ported (bass-reflex) speakers do. Some listeners have seemingly come to regard an extra bit of bass emphasis as normal and expect it from all dynamic speakers of the 1.2’s size. While the 1.2’s bass does not sound overly damped or constricted, some listeners may find its more taut, agile performance—characteristics often associated with sealed (air-suspension) designs—to lack the “room-loading” sensation of a similarly sized ported design. Like some other listeners, though, I find the more controlled bass of many sealed enclosures, like the Sonja’s, to sound more true to life. The Sonja’s low end was full sounding but it did not overwhelm my 12.5′ x 17′ room with unruly bass. I was, to be honest, a little concerned that the 1.2 might be too large for my room when initial discussions about the YG arose. YG’s Dick Diamond and Kerry St. James, who set up the Sonja at my house, both assured me that my listening room was not too small, and they went further to say that even the larger 1.3 has successfully been deployed in rooms of roughly the same size as mine. So, audiophiles with the requisite funds and a hankering for full-range bass extension and wide dynamics, but a medium/small listening space, take note; the Sonja 1.2 just might be on your path to audio bliss.

As for the rest of the 1.2’s frequency spectrum or tonal characteristics and at the risk of sounding glib, there is not much to comment on. The 1.2 sort of defies a standard sonic spectrum break-down, as such. Sure, the 1.2 has an accurate bass, a clear midbass, a revealing midrange, and a pristine treble, but the real boon is how it weaves everything together in a very pleasant, coherent, and musically engaging manner. From top to bottom, everything sounds like a complete whole, not a clever mating of slightly different parts.

The Sonja expands the soundscape even more than I noted in my YG Kipod II review. With the Sonja, the soundstage—recording permitting—can extend a few feet beyond my room’s sidewalls. It is as if the speakers were placed 9.5′ apart rather than 7.5′ (tweeter to tweeter), as they are in my setup, and this helps to alleviate the sensation of soundstage constriction in my smallish room. Soundstage depth and height are also outstanding. On the Classic Records double-LP reissue of Peter Gabriel’s Up [Real World], the song “Growing Up” filled the entire front half of my room with massive, engrossing sound. Even though the recording must have some studio manipulations in it to cause many of the images to sound as if they are coming from places quite far away from the speakers, the listening experience was exciting and fascinating. Some recordings produced in a real space with acoustic instruments, like the Gershwin LP [Slatkin, St. Louis, RR], also filled the front part of my room—and seemingly also extended beyond the sidewalls by a foot or two. The soundstaging and detail-resolving abilities of the 1.2 have the effect of enlarging the soundscape and then allowing the listener to peer into a spatially clarified and realistically focused soundfield, giving the individual images and the spaces around them greater life and realism. As such, a listening session can become more a participatory and contemporaneous experience rather than an academic exercise in observing a past event through a recording. YG’s “DualCoherent” crossovers, its ultra-rigid and lightweight “BilletCore” cones, and “FocusedElimination” cabinet-damping techniques—and other technologies—must have some merit.

Even with its exemplary frequency range and dynamic abilities, the level of detail retrieval is, most likely, what most listeners will notice first. The Sonja just seems to unravel recordings in all their beauty or drama or aggression or whatever else the musicians and producers had in mind. The 1.2 does not give me the impression of being tuned in some way to dazzle the listener with a hyped-up sense of resolution. In some regards, this “unforced ease” can make the Sonja come across as rather calm and unremarkable. But, like a musician who makes a technically difficult piece of music seem to radiate effortlessly from his or her very being, the ability of a speaker to seemingly do very little harm to the signal and to seemingly communicate the essence of the music is actually a great accomplishment. Accordingly, the long-term listenability of the Sonja is simply marvelous, even though it can also deliver very high levels of resolution.

Mind you, if a recording has a particular tonal emphasis or other shortcoming, the Sonja will tell you, but it won’t scream foul and necessarily render such recordings unlistenable. In fact, I found some of my borderline poor recordings to sound less grainy and more musically interesting through the Sonja than through any other speaker I’ve had in my system. I presume this quality has a lot to do with the Sonja’s ability to lower the noise floor. To brazenly borrow from Senior Writer Anthony C. Cordesman’s fabulous review of the YG Hailey 1.2 in Issue 252, “It shows that true resolving power is inherently musical, unless there really is something wrong with the recording.” I wish I had come up with something close to that statement on my own. To my mind, it captures much of what high-end audio is all about and describes much of what the Sonja 1.2 delivers, just as the Hailey 1.2 also apparently did for AHC.

Brief Comparison with the Hailey 1.2
YG demonstrated three of its current offerings in succession with the same gear and recordings for direct comparisons when I visited the YG factory in December of 2014: the $24,300 Carmel 2, the $42,800 Hailey 1.2, and the $72,800 Sonja 1.2. Everything AHC said about the Hailey 1.2’s considerable resolving powers were very much in evidence in that demo, and so I heartily concur with him. As well it should, the more expensive Sonja 1.2 exceeds the Hailey’s already high bar in overall resolution, and enlarges the soundstage and adds some notable heft and bass presence to the bargain. Is the increased resolution, soundstage expansion, and sonic solidity of the Sonja 1.2 vis-à-vis the Hailey 1.2 worth the additional $30,000? If one can afford it, by all means, yes! I was simply amazed by the Sonja’s musical powers in that comparison. The Hailey is a marvelous performer in all the ways my esteemed colleague described, but hearing the Sonja directly after it impressed me more than I initially thought possible.

Caveats
The Sonja 1.2 is heavy (just under 300 pounds each) and may be too large for some rooms, although as already noted, it is easier to place in small to medium-sized rooms than some smaller ported designs. While it is not as difficult to power as many speakers out there, it is probably best driven by a fairly stout solid-state amp, and will most likely not be a medium-powered tube amplifier’s best friend. The updated, more curved, softer aesthetics YG has applied to all of its current models are a clear improvement over the former boxy look, but I can understand how some folks might still find the “large metallic object” vibe of any all-aluminum speaker of its size leaves their hearts unmoved. The Sonja also pretty much demands the best electronics and cabling you can possibly assemble to fully realize its musical abilities—and so, in a way, this adds further to the already considerable cost of ownership. As mentioned, some listeners may prefer the more “room-loaded” bass sound of a typical ported design, although I find the Sonja’s bass exemplary in impact, extension, tunefulness, and all the rest.

Conclusion
The Sonja 1.2 is revealing without sounding exaggerated. It is dynamically alive without sounding forced. It is tonally neutral without sounding clinical. It can make music playback evoke deep emotional connections and spark your imagination. I certainly have had some wonderful musical experiences with the Sonja in my system. The Sonja 1.2 delivers such high sonic performance, and does so on so many levels, that it leads me with the obvious conclusion of my highest recommendation. Stunning.

SPECS & PRICING

Driver complement: One 1″ YG soft dome tweeter, two 6″ YG BilletCore mid/woofers (main module), one 10.25″ YG BilletCore woofer (bass module)
Frequency response: From below 20Hz to above 40kHz
Sensitivity: 88 dB/2.83V/1m
Impedance: 4 ohms nominal, 3 ohms minimum
Recommended amplifier power: At least 60Wpc
Crossover points: 65Hz and 1.75kHz
Cabinet: Aircraft grade 6061-T651 milled aluminum
Dimension: 13″ x 51″ x 25″
Weight: 296 lbs. each
Price: $72,800

YG ACOUSTICS LLC 
4941 Allison, St., Unit 10
Arvada, CO 80002
(801) 726-3887
yg-acoustics.com

Associated Equipment
Analog source: Basis Debut V turntable & Vector 4 tonearm, Benz-Micro LP-S cartridge
Digital sources: Ayre C-5xeMP universal disc player, HP Envy 15t running JRiver MC-20, Hegel HD12 DAC
Phonostage: Ayre P-5xe
Linestage: Ayre K-1xe, Hegel P30
Integrated amplifier: Hegel H300 and H360
Power amplifiers: GamuT M250i, Hegel H30
Speakers: Dynaudio Confidence C1 Signature, YG Acoustics Kipod II Signature Passive
Cables: Shunyata Anaconda ZiTron signal cables, Nordost Heimdall 2 USB, Audioquest Coffee USB and Hawk Eye S/PDIF, Shunyata Anaconda S/PDIF, Shunyata Anaconda and Alpha ZiTron power cords
A/C power: Two 20-amp dedicated lines, Shunyata SR-Z1 receptacles, Shunyata Triton and Typhon power conditioners
Room treatments: PrimeAcoustic Z-foam panels and DIY panels