Magnepan Magneplanar MG1.6/QR loudspeaker Page 2

Technology
The MG1.6/QR's family tree can be traced back to my MG1s, but Magnepan's driver technology and designs have evolved so far that it would be a stretch to call them "descendants." The look is familiar, however, and the large planar configuration still draws attention. Even guests with years of exposure to audio exotica at Casa Damkroger y McKenzie are taken aback by the Maggies. "That's a speaker? How does it work? Can you hang it on the wall?" Combined with the awesome VPI TNT and the wall-of-tubes VTL Ichibans, the '1.6/QRs make quite an impression on the uninitiated.

The '1.6's outward appearance is standard Magnepan: a slim, elegant panel about 5' 6" tall, 19" wide, and 2" deep. My pair was covered in off-white cloth, with inset cherrywood side trim. The terminal panel is centered at the bottom of the back side, and the '1.6 is biwirable. The terminals accept only banana plugs, but Magnepan supplies an adapter to allow the use of speaker cables with spade lugs.

The '1.6 is a two-way design that crosses over at 600Hz. The speakers are mirror-imaged, the 9"-wide bass portion running up the inside of each panel from about 11" off the floor to 61" up, and the 2" by 48" tweeter adjacent and outboard. The bass driver is a planar magnetic design, specifically a 9" by 50" section of the 0.5-mil-thick Mylar diaphragm, attached to the frame around its perimeter. The grid of wires that carries the audio signal is affixed to the diaphragm; it interacts with an array of magnets attached to a screen just behind the diaphragm.

Magnepan refers to the tweeter as a "Quasi-Ribbon" design to distinguish it from both the planar magnetic driver and a "true" ribbon of the sort they use in the MG3.5/R. The Quasi-Ribbon uses the outer 2" of the same 0.5-mil Mylar diaphragm as the bass panel with "some tricks along the intersection to avoid IM distortion," according to Wendell Diller. The signal is carried by wide aluminum-foil traces rather than wires, so that a much greater portion of the driver's surface area is actually driven. The MG3.5/R's true ribbon, in contrast, is suspended only at its ends, and the signal is carried by the driving element itself, as opposed to an appliqué of aluminum.

Compared to the MG1.5/QR, which preceded it, the '1.6 incorporates two major changes, according to Diller: "The first is that the Quasi-Ribbon driver is increased in size, which allows the crossover point to be shifted about an octave lower, so that the Quasi-Ribbon covers more of the midrange." The second is that the midbass has been improved by refinements in the damping and tensioning systems used to control panel resonances, refinements that Diller laughingly refers to as "black art."

The design of the MG1.6/QR, and of Magnepans in general, gives rise to some unusual characteristics. First of all, there's no box, hence no box resonances. Second, the '1.6 is a dipole radiator, meaning that its rear-firing wave front is exactly out of phase with the front. Combined with the driver's large area, this results in a more or less planar wave front at low frequencies instead of a traditional dynamic system's omnidirectional radiation. Imagine a barn door moving back and forth, as contrasted to an expanding and contracting ball.

Thus, the Maggies and typical speakers will load a room very differently, and get different levels of bass reinforcement from walls behind and beside the speaker. One result is the articulate midbass that Magnepans are noted for; another is that large, planar dipoles can seem to have less bass than they should do, due to cancellation between the front and rear wavefronts as they overlap around the edges of the panel.

Setup
An integral part of Magneplanar lore is that they're difficult to set up. True? Well, yes and no. Yes, they're unusual, and yes, small adjustments do make a big difference. But no, it's not really difficult to do, and the factory instructions are pretty straightforward. Besides, Maggies sound pretty good right out of the box—a few feet from any adjacent wall, a little bit of toe-in, and voilà—you're ready to listen.

The next step is to follow the manual's instructions, which will give you pretty close to the smoothest response you're going to get, and a decent soundstage. Beyond that, it's just a matter of careful listening and progressively smaller movements, down to about ½" at a time. I ended up with the speakers' outer edges 4' from the front wall and just under 58" from the side walls. For reference, my unbox'n'plop-'em-down distances were 4' 6" and 5', respectively.

My listening chair is approximately 7' from the rear wall, which places me about 11' from a line drawn between the speakers. Both speakers were toed-in slightly, with their axes intersecting perhaps 10' to 12' behind my head, and the right speaker angled in slightly less than the right. My ear height is about 40", midway up the '1.6's panels. I got the best results from the Maggies with VTL Ichibans and a biwire combination of Synergistic Research Resolution Reference on the bottom, Designer's Reference on top.

The room has been treated with panel resonators in the front corners, and Echo Busters bass traps in the front and rear corners. I also use Echo Busters diffusers behind the speakers and listening chair, and their absorbers on the side walls at the first reflection point. Each pair of speakers was burned-in for 200 hours.

Company Info
Magnepan
1645 Ninth Street
White Bear Lake, MN 55110
(800) 474-1646
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