The Fifth Element #6 Page 3
Wilson Benesch was a pioneer in the use of carbon fiber in its turntables' tonearms. Increasing experience in using carbon fiber's combination of low mass, high rigidity, and high self-damping led WB to develop the breakthrough ACT (Advanced Composite Technology) One loudspeaker, the cabinet of which was predominantly carbon fiber. WB's rather imposing "statement" loudspeaker, the Bishop, which I have heard at great length and have been enraptured by, upped the technological ante by emplacing four pairs (per speaker) of WB's proprietary Isotactic polypropylene bass drivers in a direct-coupled isobaric (clamshell push-pull) array (footnote 4). Had I had a spare $30,000, I'd have bought them.
The much smaller, stand-mounted Discovery combines the Bishop's midrange (positioned on the front baffle but at the top) and tweeter (a ScanSpeak Super Revelator, positioned below the midrange) with one pair (per speaker) of the Bishop's isobaric woofers. What makes the Discovery a new-departure design is that the isobaric woofer pair is mounted through the bottom surface of the cabinet, hence the need for a unique integral arrangement of backbone and stand.
(I suspect that one advantage of this arrangement is that, as the woofer approaches the top of its assigned frequency range and its output is presumably less linear, the less-desirable products are confined to an increasingly narrow window that the listener is increasingly off-axis to. Clever. Wilson Benesch's owner's manual makes the point that a front-firing woofer's motion risks imparting enough reaction energy to make a conventionally designed speaker's cabinet—and midrange and tweeter—rock forth and back, to the detriment of imaging and detail. The Discovery's radical design confines the inertial and reaction forces associated with its woofers' motion to the vertical axis, where gravity exerts a powerful damping force on cabinet motion. Doubly clever.)
The Discovery's enclosure has two ports, of equal diameter but unequal length. The outermost bass driver faces inward, so its basket and magnet structure are visible. The cabinet's front-to-back profile is composed of Wilson Benesch's familiar tapering arcs. The front has a detachable black grille, while the sides show black carbon fiber. The stand's backbone and base are aluminum with a silver polymer finish.
The enviable hallmarks of Wilson Benesch's loudspeaker sound—and the Discovery falls right into line—have been truly exceptional coherence, of the kind usually associated only with panel speakers; seamless transition between midrange and treble; vanishingly low distortion; and imaging and soundstaging that can bring you up short. What has enchanted me most, though, is a beguiling combination of warmth, roundness, and fullness of musical tone, with a seemingly paradoxical absence of veiling or time smear. Indeed, I don't think I have ever heard as long a "tail" on the end of John Atkinson's solo-electric-bass phase test (on Stereophile's Test CD 2).
There is usually a minus side to every ledger, though, and in WB's case it has consisted of: bass that does not extend quite as low as American tastes and home construction methods seem to require; the need for amplification with stalwart current and damping; and prices at the top end of each product tier. Although, in WB's defense, I can say that unless you've heard the Bishops powered by a powerful amplifier that reliably keeps doubling power down to 2 ohms, you probably haven't heard all the bass they're capable of. And the clamshell woofers do give the Discoverys substantially more bass than the ACT Ones and Twos.
Perhaps one reason that Wilson Benesch (and other makers of truly fine and musical loudspeakers) has failed to get traction in the US retail market is that sales may go to speakers that cost 15-20% less, and are more "impressive" in a brief audition in a dealer's showroom.
Picking out details is impressive, and it can be wonderful. But it is of even more lasting value to be shown how the details fit together to form a comprehensible whole. Perhaps it is packing all the acoustical centers of the drivers into such a remarkably tight compass that does the trick. But however it's done, on Ella's "Easy to Love," Grex Vocalis' "Innsbruck," Mary Black's "No Frontiers," and other favorites, the Discoverys set new standards for integrating musical details without obscuring them.
Next time: "Truth or Consequences with Glenn."
Footnote 4: Non-clamshell isobaric loading is possible, but presents substantial engineering challenges due to nonlinearities of driver motion and the varying hydrodynamic behavior of enclosed air volumes at varying frequencies. Clamshell disposition of the drivers reduces to a minimum the volume of air that is relied on to exhibit pistonic behavior.