Zellaton Reference MkII Loudspeaker

Over the last twenty-five years I’ve heard a lot of fine equipment at trade shows around the world. Only twice have I been stopped in my tracks by a sound so uncannily realistic it literally made me do a double take. This happened, a decade or so ago, at CES with the Scaena Iso-Linear loudspeaker array. And again, just three years past, in Munich with an earlier version of the speakers I’m about to discuss, the Zellaton Reference MkIIs. In both cases I was so amazed that, one by one, I tracked down every other member of our staff and dragged him back with me to hear what I’d heard. It should go without saying that, in both cases, I immediately asked for review samples.

Alas, the Scaenas didn’t fulfill their promise in my listening room (not wholly the speakers’ fault, BTW), but the Zellaton References, now in their MkII iterations, are a different story. Before I tell that story, you should know that the Reference MkIIs are not for everyone, and I don’t just mean because of their incredibly high price tag ($150k per pair). Unlike several other truly great loudspeakers, the Reference MkIIs are targeted quite specifically at one kind of listener and one only—the kind this magazine was dedicated to at its founding. If your taste runs to classical music, large-scale or small, or acoustic music from jazz to pop, then the Zellatons have certain virtues that other transducers—even other far more expensive transducers—don’t have (or don’t have to the same extent). If, on the other hand, you’re into rock, electronica, or other types of hard-driving amplified music—or if you simply can’t live without the whip-crack transients and midbass slam that certain speakers deliver in abundance—you can do better than the Reference MkIIs for a lot less money.

So, why would anybody in his or her right mind contemplate purchasing speakers that cost a fortune and have limited appeal? Well, for the two or three of you who are still following this blog with genuine interest (or morbid curiosity), let me see if I can come up with an answer.

To begin with, the Zellaton Reference MkIIs don’t sound like any other dynamic loudspeakers I’m familiar with. Indeed, at their best, they don’t sound like loudspeakers at all. They simply haven’t got the usual metal, plastic, paper, ceramic, diamond, or carbon-fiber cone-in-a-box sonic signature. For better (and a bit of worse, as you’ll see in my full review), they are almost as colorless as the air in your listening room. Indeed, if you were to blindfold yourself (as a few of my online critics would prefer I do—and gag myself while I’m at it) and then try to guess what you were listening to, you would probably say an unusually neutral, three-dimensional, deep-reaching, full-bodied electrostat or, with select recordings of voices and instruments played back at the right volume levels, the real thing.

To explain why the Zellaton drivers are so exceptionally low in material coloration and so seamlessly matched from woofer through tweeter that they sound like a single-driver ’stat (or the real deal) requires a bit of a history lesson. And, as it turns out, only a few other companies still extant have a longer history than Zellaton. Even though you’ve likely never heard of this little German marque (based in Munich), its pedigree dates back to June 9, 1930, when its founder, German engineer and physicist Dr. Emil Podszus, filed a patent on what was then the first “sandwich” cone driver.

Nearly ninety years later Emil’s grandson Manuel Podszus is still making his grandfather’s drivers—and still making them by hand in a process so painstakingly exacting that it takes several weeks to complete each cone. It is commonplace today for loudspeaker manufacturers to brag about their high-tech tweeters, midranges, and woofers, but, frankly, a good deal of the fabrication and assembly of those drivers is farmed out to specialty companies that have the machinery to produce diaphragms, spiders, voice coils, and magnets precisely to order—and in sufficient quantity. This is not the way Zellaton works. It makes diaphragms the way Patek Philippe makes watches.

The Reference MkII is a three-way floorstanding loudspeaker with a single 2″ true cone tweeter (not a dome or inverted dome but a cone), a single 7″ mid/woofer (which, by itself, covers the range from 200Hz to 6.5kHz—part of the reason why the Reference MkII sounds so much like a single-driver speaker), and three 9″ woofers, all housed in a unique, gorgeously finished, multi-layered, matrix-braced, open-backed enclosure (see below for more details). Every single one of the Reference’s drivers uses Emil Podszus’ sandwich cone (which his grandson Manuel has improved by “using modern materials and sophisticated, purpose-designed processes without changing the basic formulation that has been employed for decades”). Utilizing a single type of driver made of precisely the same materials—rather than a mix of cones and domes made of a variety of materials, as is the case with almost every other dynamic or hybrid loudspeaker I know of—is another reason why the Zellaton Reference MkII sounds so remarkably ’stat-like and of a piece.

What is a Zellaton driver? Essentially, it is a three-piece sandwich cone comprising a micro-thin layer of aluminum film (0.006mm thick in the case of the tweeter) atop a layer of ultra-stiff aerated foam (still handmade and hand-cured using Emil Podszus’ “top-secret” formula), and backed by a proprietary layer of treated paper. Zellaton cones are incredibly light (the Zellaton tweeter’s diaphragm weighs approximately 0.16 grams!) but also incredibly stiff, giving them what is claimed to be “ideal pulse response.” All of the Reference’s drivers also use computer-optimized magnet systems; proprietary spiders and surrounds; and high-temperature voice coils on titanium-film formers. Each driver is “subjected to multiple control measurements and fine adjustments,” with its frequency response logged and documented and pairs matched to the highest tolerances. The drivers are linked to each other via crossover networks that use ultra-high-end Dueland Coherent Audio caps, coils, and resistors, and wired with ultra-high-end Schnerzinger cable.

The Reference MkIIs’ enclosures are just as handcrafted as their drivers. Intricate in design, damping, bracing, composition, and finish, their multi-layered walls vary in thickness from 34mm to 50mm. At the rear, the speaker is mostly open from top to bottom—an unusual configuration that reduces or eliminates compression of the tweeter, midrange, and woofers’ backwaves, and gives the Zellatons something very like the dipolar radiation pattern and easy, boxless openness of membrane speakers—another reason why the Reference MkIIs sound like ’stats on steroids.

Of course, the main reason that the Zellaton Reference MkIIs are reminiscent of electrostats is the forehead-slapping realism with which they reproduce voices and so many acoustic instruments. This is in equal parts the result of extremely high resolution (virtually as high as you can get at low to fairly loud levels, I think, with cones or membranes), extremely lifelike reproduction of timbre, extremely natural and linear reproduction of transients (with none of the edge or “zip” of metal domes and none of the subsequent timbral, dynamic, and imaging discontinuities between the midrange and the upper octaves—every instrument speaks with the same voice no matter where in its range it plays, just as in life), and extremely low driver/box coloration (with none of the usual sense of the box or the backwave of the drivers selectively adding spurious, spring-like energy to the presentation, which, despite the manifest increase in thrills this “super-charging” gives the sound, is not something one—or at least this one—hears in a concert or recital hall).

With really great recordings of acoustic music, the result is a truly remarkable sense of being in the presence of actual vocalists and instrumentalists. As I’ve noted before, this level of realism—where a voice or an instrument is conjured up so completely that the mind does a double take—is not something we are used to from stereo systems. We expect hi-fi’s to sound at least a little like hi-fi’s. It is what they are, after all—and hell, we’re looking right at them. In spite of this, at its best the Zellaton Reference MkII makes you forget where the sound is coming from.

I will have a good deal more to say about the Zellaton Reference MkII (including a section on what it doesn’t do as well as other dynamic loudspeakers) in an upcoming issue of TAS. But, for the nonce, if you’re a lover of acoustic music and a connoisseur of handmade objets d’art (and, oh yes, have a boatload of cash), you should get in touch with Gideon Schwartz of Audioarts in NYC at (212) 260-2939 or info@audioarts.co. You won’t regret it—trust me.