More than any other electrostatic speaker of its era the KLH Model Nine was the watershed moment that proclaimed the full-range ’stat had indeed come of age. The vision of peripatetic designer and collaborator Henry Kloss (his fingerprints are also on this list’s AR3a and the Double Advents), the Model Nine and its more potent iteration known by well-heeled owners as Double Nines, is significant in that it took the transcendent qualities (midrange transparency, resolution speed, and low distortion) of the parlor room-restricted Quad ESL and added properties like 40Hz bass extension and improved output. But this six-foot dipolar had an attitude—fussy about placement and greedy for power, it blew fuses with regularity. It could be beamy in the treble, too, but when all the stars aligned few cone speakers could match this naturalistic combination of liquidity, speed, and power, making it the rare companion able to capture near symphonic playback levels. The Model Nine has been the inspiration for virtually every planar-style loudspeaker since.
This was the last version of the original Infinity Reference System, and, by any measure, the best, standing second to none in frequency range, in a top-to-bottom coherency that had eluded designer Arnie Nudell in the earlier three versions (yes, three, there was no IV), and in an overall faithfulness to the real thing that exceeded Nudell’s best previous efforts. The EMIT tweeters had been considerably updated (so that there was less grain, less artificial brightness, and a sound just a few steps below that of Jim Winey’s Magnepan true ribbon); the EMIT and the ENIN midranges (a replacement for the Series One’s bipolar ribbons) were both now planar “ribbons”; and the non-Watkins graphite-fiber woofers, all 12 of them, were now powered by a 2000-watt amp (up from 1500 in the Series III). What this, finally, accomplished, along with a few other mods, was a seamless sonic transition between the bass and the upper drivers—a first in a Nudell product. A dream realized and a dream for this listener.
Of all the loudspeakers I’ve heard in a lifetime of listening, the large, three-panel Maggie 1-Us—Magnepan’s first widely marketed planar-magnetic speaker—remain the most memorable. I’ve told the story several times before of how I originally (and unwittingly) auditioned these speakers in the early 70s and—not knowing what a Magneplanar was back then—assumed that the real grand piano ensconced behind the “screens” at the far end of the listening room was making music when, in fact (and of course), it was the Maggies that were doing same. I’ve never again been fooled that completely by a loudspeaker because nothing I’ve heard since then has sounded that much more like the real thing than the Maggie 1-Us did at the dawn of the high-end era. As HP put it in his ground-breaking TAS review: “The Magneplanars are…[a] ‘classic’…a speaker that is and will be a standard by which and to which others will be compared.” And so they were, and so they still are, in certain key respects (such as midrange realism and mid-to-upper bass resolution, scale, and slam), to me.
One should always be wary of pronouncing “firsts,” but, appearing in the early seventies, Jon Dahlquist’s DQ‑10 was to my knowledge the first dynamic speaker to employ multiple drivers in an open-baffle configuration (except the acoustic‑suspension woofer, which was enclosed) staggered for proper time‑alignment and phase coherence, in an attempt to realize the openness and freedom from boxiness that Dahlquist prized in his beloved Quad ESL-57s—with the added advantages of deeper bass and dynamic extension well beyond the Quad. (The physical resemblance to the Quad was both mandated by the design and an intentional homage.) Far from flawless (including conceptually), the DQ-10 was nevertheless a ground-breaking design that preceded dozens of subsequent speakers (perhaps most prominent among them models from KEF, B&W, Spica, Thiel, Vandersteen, and Wilson) continuing up to the present day. Few large, full-range dynamic speakers before or for some time afterward equaled its openness.