March 1, 2009

Von Schweikert Audio UniField 3 Loudspeakers

I’ve long admired the loudspeakers made by Von Schweikert Audio, having stumbled into a demo about 25 years ago when I lived in Southern California. Albert Von Schweikert himself was then still a lab assistant at Cal Tech, building in his garage a speaker that he called the Vortex Screen ($750/pair in 1983): four drivers mounted on a board and clothed in stretch polyester double-knits. He would haul them around with a crew of students from his lab and set them up in private homes, audio stores, and record shops. I wandered into the Claremont Folk Music Center one sunny afternoon, and "Professor Von Schweikert," as he was introduced, was speaking softly as his crew lifted the tall, mysterious-looking speakers from a dolly and set them up on platforms. Each was the height of a 6’-tall man, though only about 2’ wide. Once hooked up, they played soft, they played loud, they played spooky, spacious real. I’d never thought audio could capture both the body and soul of music before; after that demo, I was a believer.

Now, after having established his famous Virtual Reality line of speakers, from the ever-popular VR4 JR Anniversary ($5995/pair USD) on up to the statement VR9 SE ($90,000/pair) -- each a four-way model, with that deep two-box, sloped-tweeter-cabinet look -- Albert Von Schweikert has developed a completely new approach to design and appearance. That approach is now embodied in a small, three-way floorstander that he calls an "augmented one-way," which he claims plays convincingly in small rooms but can also command larger ones. It’s called the UniField 3 ($15,000/pair), and it began shipping after debuting at the Rocky Mountain Audio Fest in October 2008.

Baby-grand looks

The UniField 3 is a two-box speaker of moderate dimensions (40"H x 10"W x 14"D) and weight (82 pounds). The manual lists its sensitivity as 88dB at 8 ohms (average, anechoic chamber), and claims an impressive frequency response range of 32Hz-40kHz. The recommended range of amplification is 20-300W, with neither tube nor solid-state amps particularly favored. However, the specs on the Von Schweikert Audio website claim in-room sensitivity to be a very tube-friendly 91dB at 8 ohms. Whatever the UniField 3’s sensitivity, it demands only moderate power.

My review pair’s modest dimensions, glossy ebony finish (natural cherry is also available), and gently curved sides made me think of a Steinway baby-grand piano. The UniField 3’s looks are stunning -- modern and even more attractive (to my eyes) than the wood-sculpted lines of other VSA speakers. The sleek, springing-panther profile of each stack suggests they’d find perfect placement and give chic, complementary accents to trend-setting, postmodern décor in remodeled loft spaces in SoHo or Milan. I’d give Von Schweikert an A+ in industrial design for this one.

But under its gleaming skin, this svelte beast is a new one altogether. By calling the UniField 3 an "augmented one-way" speaker, Von Schweikert means that its 5" "full-range" driver covers frequencies from 70Hz all the way up to 15kHz. The full-range cone is augmented by a 7" woofer and a 3" ribbon supertweeter; the crossover frequencies are 100Hz and 8kHz.

"My reference in design was a one-way Quad electrostat," Von Schweikert said when we spoke on the phone recently. "I wanted the same clarity and coherence from a cabinet-loaded speaker, so I thought of single-cone speakers pioneered by Lowther and decided, ‘Why not a modern copy?’"

The composite 5" full-range cone, with forged aluminum frame driver, was designed in Japan by Fostex. The extremely low-mass, French-designed 3" aluminum-foil supertweeter is there only to augment the highs over 8kHz, providing airiness and spatial cues. The Norwegian-made 7" Seas Excel magnesium woofer, which sits in its own triple-chambered transmission-line enclosure, acts as a subwoofer. All the drivers are made to Von Schweikert’s specifications and modified specifically to work together in the UniField 3. The 7" woofer is coupled to the room by a front port (2" wide with a 3" flare) tuned to 32Hz to extend the bass response.

These cabinets are substantial -- the triple-wall design comprises a sandwich of materials that together cancel vibrations. VSA begins with low-Q MDF, specially molded to have curved sides. Then, to dampen the MDF, artificial stones of a complementary high Q are glued to it. There are a total of 18 pounds of these 3/4"-thick stones in each woofer cabinet, and 2.4 pounds of 1/2"-thick stones in each tweeter/full-range-driver (T/F) module. The third layer is heavy, 1/2"-thick black felt. The result is a highly damped, measurably zero-vibe cabinet with a curved interior that breaks up the standing waves that might otherwise resonate.

Albert Von Schweikert shows how the UniField 3's walls are constructed at CES 2009.

On the back of each T/F module and woofer cabinet is a set of five-way WBT Next-Gen rhodium binding posts. Finally, each box has light, fiberboard-framed grilles covered in attractive and functional black cloth. These magnetically attach to the front baffles of the woofer cabinets and T/F modules.

Setup and operation

The UniField 3s came packed in three cardboard cartons (one for each woofer module plus stands, and one for both T/F modules) reinforced with lots of polystyrene, foam, and plastic. It was easy to lift each component out of its box and set up the U3s in my smallish listening room (12’ x 15’ x 8.5’), which doubles as my study. Assembly took less than 10 minutes per side, most of that time spent screwing the three carpet-piercing spikes into each base and then leveling them. Maneuvering was a cinch, as the woofer cabinet weighs about 56 pounds, the T/F module only 19 pounds, and the stand 8 pounds (per my bathroom scales). To move them around to find their optimum positions, I simply lifted the T/F box off the top of the woofer cabinet, set it aside, then lifted the woofer box off the three-point stand, repositioned the stand, then restacked the two boxes.

Proper acoustic alignment is achieved simply by placing the front baffle of the T/F module 1" back from the front seam of the woofer cabinet. My speaker modules came with vinyl bumpers attached; it was easy to lock the cabinet down to stand and the T/F module down to the woofer module. However, I’m told these bumpers have already been discontinued; future runs of the UniField 3 will be provided with strips of white damping putty to be applied by the user.

As the UniField 3s are biwired, setup entailed using a pair of 12’, internally biwired, Von Schweikert Master-Built Signature speaker cables ($5400/pair) provided me by VSA. It was a fine, mechanical pleasure to hook them up -- no twisting, bending, or fussing of any kind, then a tidy snick as each spade slipped into place. Though the cables arrived pre-cooked at the factory, they took another 250 hours to completely burn in. Once they did, they sounded quite organic and natural, without glare or peakishness, and open enough that the lovely inner details of orchestral sound and fine tremolos of vocal recordings were evident. I highly endorse them, especially in a system with the UniField 3s.

The UniField 3s themselves were amazingly sensitive to positioning, and reacted negatively to toe-in with all three of my amps. At first, I tried them in the same spots where I place my reference speakers: about 8’ apart, 28" from the front wall, and toed-in about 20 degrees, so that the axes of the drivers converged exactly at my listening position about 9’ away. This sound instantly proved too harsh -- the energy from the full-range drivers and ribbon tweeters was too prominent, throwing off the tonal balance. I toed the speakers in even farther, so that their axes converged about 2’ in front of my listening position, but this simply confused the imaging, compressed the soundstage, and muddled orchestral music. I then tried moving them back, until they were only 6" from the front wall (as the manual suggests they can be), but that produced a sound I felt was confused in my small room, as though listening through a sonic funhouse mirror. These last positions did increase the bass output, but, in my room, it put the speakers too far into the corners and against other surfaces that blocked proper dispersion. In the end, I placed the UniField 3s 9’ apart and their front baffles 28" from the front wall, firing almost straight ahead with a toe-in of only about 1". Their timing, tonal coherence, and imaging all snapped into place. After trying a few variations, I found I most preferred running the speakers with the woofer grilles off and the T/F grilles left in place.

But the bass was still lacking, so I called the factory. Albert Von Schweikert told me that, for the UniField 3’s first production run (which included my review pair), they’d stuffed the lower woofer cabinets with Dacron polyfill, to tune the speaker to be placed up against the walls of small apartments. Subsequently, they’d found that most customers preferred pulling the speakers out into the room. So did I. Von Schweikert said that the bass can be "tuned" by adding or subtracting Dacron polyfill, and that if I wanted to have more bass with the speakers placed farther out into the room, I’d have to remove all the Dacron. In my room, I only wanted more deep bass and slam, so he told me to take a wire coat hanger, bend it 90 degrees 1" from one end, insert this hook into the port, twist it around until all the Dacron was wound around the shaft, then pull it all out. I did.

Wow! Did that make a wonderful improvement. Removing all the Dacron clogging up the bottom cabinet behind the port instantly did the trick -- I was completely happy with this development. From now on, Von Schweikert said, all UniField 3s would be shipped without Dacron filling the lower chamber of the woofer cabinet.

The UniField 3s came with a three-page instruction manual that was revised as I wrote this review. The new version is very detailed and reflects improvements developed after VSA shipped the first production run. It gives clear and explicit instructions regarding unpacking, assembly, and placement of the speakers, along with a helpful explanation of how to tune the woofers for different spaces. It also recommends loading the stands with lead or iron shot -- a mod I didn’t try.

System

I installed the UniField 3s and Von Schweikert’s Master-Built Signature speaker cables in my system in place of my Von Schweikert VR5 HSE speakers and Verbatim cables. The rest of the system consisted of a Herron VTPH-2 phono stage, deHavilland Mercury 3 (on loan) and Thor TA-1000 Mk.II preamplifiers, deHavilland Fisher 50A monoblock power amps (in for review), Musical Fidelity A3.2cr and VAC PA-80/80 stereo amplifiers, Cary 303/300 CD player, a Nottingham Spacedeck turntable (with heavy kit) with Spacearm tonearm, and a Zyx Airy 3 cartridge (.24mV). All rested on a Finite Elemente Signature Pagode five-shelf rack. I use Vibrapods under the turntable plinth and Cerapucs under the CDP. When the VS VR5 HSE speakers are in the system, they’re isolated with Vibrapods under them, which in turn sit atop 3/4"-thick boards of MDF.

Interconnect cables were Cardas Golden Reference from phono stage to preamp, Analysis Plus Solo Crystal Oval from CD player to preamp, and Cardas Golden Cross from preamp to amp(s). (I’d tried a variety of interconnects before settling on the Cardas/Analysis Plus combo as the most balanced without losing significant detail.) Power cables were a mix of Fusion Audio’s Impulse and Predator, Harmonix XDC Studio Master, and Cardas Golden Reference. Preamps were plugged into a Balanced Power Technology Clean Power Center passive line filter, while amps and CD player went straight into Oyaide R1 wall outlets on separate dedicated 15A lines.

I found that the UniField 3s liked both of the tube amps I tried: the 40Wpc deHavilland Fisher 50A monos (KT88 tubes run in class-A triode mode, $7250/pair) and the 80Wpc Valve Amplification Company PA-80/80 (KT88s run ultralinear). However, the 130W Musical Fidelity A3.2cr solid-state amp, though fabulous in terms of midrange body and bass, seemed to produce too much treble energy, sounding incisive and causing listening fatigue. The Fisher 50A monos were splendid for small-combo and big-band jazz, rock, solo piano, and chamber music, but for consistency of play through complex choral and orchestral music, and for handling dynamic operatic passages without losing resolution, tonal color, and clarity, I preferred the venerable VAC PA-80/80. Moreover, the 80Wpc VAC better controlled the bass, giving it texture, nuance, and articulation. Most of my listening, therefore, was with the VAC.

Concert-grand sound

Once optimized for my room and driven by the 4-ohm taps of the VAC PA-80/80 stereo amp, the compact and gorgeous UniField 3s produced a grand, lively sound competitive with larger speakers. Whether from LPs or CDs, the sound I got was smooth, coherent, and resolving, with impressive dynamics and bass.

In talking about dreaming up exactly how he’d deploy U3’s single 7" woofer, Albert Von Schweikert said, "I wanted to design a small speaker that, though still compact, could still go down to 32Hz -- capable of rendering that second note on a church organ."

In my listening, I found his ambition realized. I measured full output in-room to 31.5Hz, testing the sound-pressure levels with the Stereophile Test CD and a RadioShack hand-held SPL meter placed about 9’ from the speakers, on one arm of the couch on which I sat to listen. On 1/3-octave warble tones at -20dB, the UniField 3s produced SPLs at a relatively flat 88-90dB from 1kHz down through 100Hz. They dropped to 82-83dB from 80 to 63Hz, bumped up to 97dB at 50Hz (probably a room mode), and output a very impressive 90dB at 31.5Hz. At 25Hz, the output dropped to 84dB -- still impressive.

But what about that second note on the organ?

I played Bach’s Toccata and Fugue in D Minor, BWV 565, from organist Karl Richter’s Toccata and Fugue: Bach’s Organ Music (LP, Deutsche Grammophon 2535 611-10). The piece builds an ornate cathedral of sound on a foundation of huge subterranean vaults of bass. Here the UniField 3 was fast, resolving, and accurate almost throughout the range, just missing the deepest notes, which it rendered in strong gestures that still suggested the grandeur of the piece. The excitement was mostly all there, though. From the first forceful statements that descend downward at the beginning -- in essence one long phrase, motives punctuated by silences -- it was obvious the UniField 3 possessed all that I wanted in resolution and clarity. The slow crescendo that ends this long opening phrase began with a deep pedal note that seemed to growl upward from a cavern as the lush, rising, chromatic chord slowly saturated through the floorboards between the speakers.

As for tight bass and rhythmic timing, taut indeed were the guitar, bass, and drums of "That’s the Way of the World," from Earth, Wind & Fire’s Greatest Hits, Vol.1 (LP, ARC’s reissue of the original 1978 LP, Columbia FC 35647). The beat as articulated by the bass and drums was clear and punchy, with that light, bouncy disco drive that inspired this era to its dangerously sublime excesses of coke and couture. Meanwhile, the Fostex full-range driver proved terrifically agile, rendering all instrumentals and vocals with truthful timbres -- especially the voice of lead singer Maurice White as he slipped through baritone melismas into a close-miked growl -- Yeow! The chorus of overlaid male falsetto voices came in light and airy, forward in the mix, the horns deeper back, as if far to the rear of a stage or bandstand. And the ribbon tweeters were doing their job -- there was plenty of space around instruments and voices.

Opera can challenge many speakers: the lush and exquisite vocal timbres of singers, their full dynamic range, and their ornamental coloratura can be much too rapid, resulting in poor imaging and causing extreme congestion in the sound. Combine all of this with an orchestra, and speakers can be overwhelmed and sound confused. The UniField 3s handled operas wonderfully. The combination of full-range driver and ribbon tweeter produced such excellent imaging that, in Violetta, a live Salzburg Festival recording of selections from Verdi’s La Traviata (CD, Deutsche Grammophon B0006188-00), I could "see" soprano Anna Netrebko’s Violetta and tenor Rolando Villazón’s Alfredo sweeping and swaying across the expansive stage. As they rose to her top notes, Netrebko’s glissandi were just so slightly piquant, giving her solos their individual character. Villazón’s warm tenor came through with wonderful attack, decay, and inner tremolo detail. The strings of the Vienna Philharmonic, conducted by Carlo Rizzi, were consistently open and without hash or glare. These were indeed speakers of high refinement and wondrous transparency.

Lately, nearly every other night, I’ve been listening to Chopin nocturnes with my three-year-old daughter, from two discs of them by the fine Czech pianist Ivan Moravec (CD, Elektra Nonesuch 79233-2) -- they’ve been her lullabies. The sound is exquisitely delicate and yet harmonically rich, Moravec’s touch as light as a Venetian pickpocket’s. The U3s captured the beautiful decays of the piano notes with agonizingly beautiful strokes of feathery departure. Yet on the first, pure, rounded notes of the Nocturne in E-flat Minor, Op.55 No.2, there was spine-tingling clarity, a depth of sound, and a fineness and acuity to the microdynamics of performance that gave it tremendous drama and presence. And when Moravec ran through an arpeggio, it was as if he were laying down a pillow of clear, mountain water for my daughter to rest her head on.

Yet for all its punch and power, their airiness, transparency, and harmonic richness, what the Von Schweikert UniField 3 seemed to do best was the sweet and the lovely. It did midrange like the nesting call of a forest cuckoo. Franz Schubert’s Symphony No.5, as performed by Karl Böhm and the Berlin Philharmonic (LP, Deutsche Grammophon 139162), is a fine test of string warmth and clarity. Though scored for the light orchestra of Haydn (strings, horns, woodwinds without clarinets, no timpani), the work has passages as forceful as Beethoven. Through the UniField 3s, the string sections sounded lavish and nimble both, with sweet violins and plummy cello pizzicati. And throughout the movements, all timbres sounded natural, with good bass bloom and surges. The third movement, a minuet marked Allegro molto, is a lovely German dance with a theme that bounces from violins to cellos, back again to violins, then culminates in a forte unison of both sections. The U3s rendered all of it with delicacy and a fine warmth, tonal balance, and sweetness, ranging low enough to capture the rich character of the bass viols. The performance had true, tonal weight -- a kind of bloom of bass and midrange together -- that added up to the feel of a live performance as the music reached beyond the speakers and through the room with almost tactile bursts of lavish sound. I played this recording again and again, not having heard it rendered before with such liveliness and firm string tone.

Comparison and conclusion

My reference speakers are VSA’s own VR5 HSEs. Though discontinued some four years ago, when last available they cost exactly the same as the UniField 3s today: $15,000/pair. But while the UniField 3 is a two-box, "augmented one-way" speaker, the VR5 HSE is a conventional four-way, one-box tower with a rear-firing ambient tweeter. The front-firing drivers are a 1" Seas Excel Millennium soft-dome tweeter, a 5" Audax Aerogel midrange cone, and two Seas 7" magnesium-cone woofers of the same type used in the U3. The VR5’s cabinet is of cross-braced, 1"-thick MDF damped with 1"-thick foam rubber and felt. Like the bass cabinets of the U3, the VR5 HSE’s woofers are enclosed in a modified, triple-chambered, transmission line stuffed with Dacron to damp resonances. Unlike the U3, though, the VR5 HSE’s vent is on the rear panel, and tuned to 25Hz rather than 32Hz. The VR5’s frequency response is claimed to be 28Hz-20kHz, +/-1.5dB, and 22Hz-25kHz, -6dB (+/-1dB at midband). Its sensitivity is rated at 91dB, its recommended amplification 10-300W. In sum, I’d say the two models are technically comparable.

On the same pieces of orchestral music, with the same electronics, sources, wires, and cables, the VR5 HSEs produced a sound richer in the midrange and weightier in bass overall. There was more slam and a warmer, slower, more buoyant decay to timpani strokes. Strings were textured and tactile, woodwinds warm and articulate. Yet the VR5 HSE could sound colored in comparison to the U3 -- my ears, recently tutored by the newer speakers, kept noticing that these rich sounds were emanating from the VR5s’ cabinets. By contrast, the U3s were more transparent, its drivers "freer."

With recordings of acoustic piano, though, the VR5 HSE came into its own, producing a deep resonance, a richness of harmonics, and a slowness of decay that set it apart. I listened to the same Ivan Moravec set of Chopin nocturnes through the older speakers, and notwithstanding the U3’s superior transparency, I preferred the sense of depth and emotion, the richer and more complex harmonics of the VR5 HSE. Finally, on the disco music by Earth, Wind & Fire, the VR5 HSEs produced a bigger sound with greater soundstage depth, while the U3s had more refinement and air. Both speakers were great at pace, rhythm, and timing. When it came to imaging, however, the U3s excelled. The VR5 HSEs always had a much softer focus and could immerse the room in sound, losing soundstage definition, whereas the U3s usually presented a distinct stage and instrumental images, and cleaner space around them. Between these two very fine pairs of speakers, it was a toss-up.

Overall, though, the more I listened to the UniField 3, the more I was convinced of their worth -- how much they revealed of the mixes of many of my recordings. To say that I enjoyed my time with them would be an understatement -- I found them thrilling and revelatory. Albert Von Schweikert has made a genuine contribution with his UniField 3, creating not only a full-range speaker that will be viable in small rooms, but one that I suspect can handle larger rooms with ease. Moreover, his unique, "augmented one-way" design has resulted in a loudspeaker of supreme transparency, clarity, and imaging ability that is also capable of producing real bass down to 32Hz. In essence, the UniField 3 behaves like a single-driver speaker in coherence and palpability, and a multidriver model in terms of warmth, ambience, and slam. Within the range of speakers costing $15,000 to $18,000 per pair, this one is competitive with some of the best I’ve heard, including models from Verity, Nola, and Vandersteen. But it is also unique, reproducing a clarity and a freshness of sound unlike that from any other speaker I’ve heard. For these reasons, I name the Von Schweikert Audio UniField 3 loudspeaker an Ultra Audio Select Component.

. . . Garrett Hongo
garretth@ultraaudio.com

Von Schweikert Audio UniField 3 Loudspeakers
Price: $15,000 USD per pair.
Warranty: Ten years parts and labor.

Von Schweikert Audio Corp.
41110 Sandalwood Circle
Unit 122
Murrieta, CA 92562
Phone: (951) 696-3662
Fax: (951) 696-3663

E-mail: albert@VonSchweikert.com  
Website: www.vonschweikert.com