Magnepan MG12 and MMG Loudspeakers

The Goose and the Gander

Last issue, in my review of the excellent Focal/JMlab Electra 1007Be mini-monitor, I laid out the case for the superiority of two-way dynamic loudspeakers, which mostly amounts to the fact that they disappear more completely as sound sources than multiway loudspeakers thanks to smaller enclosures, fewer drivers, and simpler crossovers. But two-ways don’t just come in little boxes with little cones. They also come in planar form, like the two floorstanding dipoles from Magnepan that I’m about to review, and I can tell you upfront that what is good for the dynamic goose is every bit as good for the planar gander—in some ways, maybe even a little better.

The thing about planars is that they have no boxes—just wooden frames, like picture frames, to hold their parts in place. They also have next-to-no drivers. In both the Magneplanar MG12 and its littler brother the MMG, music is made by a quasi-ribbon tweeter and a planar-magnetic woofer—featherweight sheets of Mylar with very thin metal strips (or wires) attached to their surfaces. Suspended between or above stationary bar magnets, the Mylar diaphragms vibrate as the positive and negative electrical signals passing through their metallic “voice coils” are alternately attracted and repelled by the magnets.

Not only do Maggie drivers have very low mass; they also have very large surface areas. The quasi-ribbon tweeter in the smallest of these two speakers— the four-foot-high, approximately 14" wide MMG—is equivalent in surface area to seventy-two 1" dome tweeters, the planar-magnetic woofer to nine 8" woofers. Size matters here, particularly when you’re playing back big instruments like pianos and drum kits, or large ensembles like orchestras. Because of their large drivers, the MMG or MG12 don’t “miniaturize” such instruments and ensembles to the extent that many two-way mini-monitors and some multiway dynamics do. By “miniaturize,” I don’t just mean shrink their physical size; I mean reduce our sense of the amount of air they move when they play. As I’ve said repeatedly, the illusion of listening to real instruments largely depends on recreating the distinctive ways the directionality, size, and presence of those instruments changes with changes in pitch and dynamics— what I call “action” or bloom. A large line source with large planar drivers, like these two Maggies, will recreate action more convincingly than typical two-way cone speakers, while preserving (and, in some cases, improving on) the two-way’s disappearing act.

Indeed, without a box and with large, very-low-mass drivers, the two Maggies disappear into their soundfield as well as most minis. However, having no box is also a bit of a mixed blessing. As with all dipoles, these two Maggies project equal amounts of sound to their front and their rear, and you will have to cope with the backwaves of both the quasi-ribbon and planar-magnetic diaphragms in each speaker, which for better and worse (mostly for better) aren’t being “damped” by firing into an enclosure.

Theoretically, if you place a dipole far enough out into a room, the reflection of the rear waves off the backwall will be delayed long enough not to interfere with your perception of the “first arrival” of the front waves (and, thereby, not to mess up the sound with a jumble of outof- phase information). However, placing these little Maggies well out into a room may defeat their intended purpose, which is to deliver the Magneplanar virtues in a package small enough not to be obtrusive. (One of the perceived drawbacks— perceived by Magnepan, at least—of the much taller and wider Maggies, like the 1.6, 3.6, and 20.1, is what used to be quaintly called the “wife acceptance factor”—nowadays, politically corrected to “spouse acceptance factor.” Properly placed, Maggies simply dominate a room, and some folks find two freestanding monoliths sitting in the middle of their floor a little too 2001: A Space Odyssey.) Happily, a bit of damping behind the speakers, like a wall hanging, can solve the backwave problem (which, to be fair, isn’t restricted to dipoles).

One of the things that dipoles don’t have issues with (and box speakers generally do) is sidewall reflections. The Maggies’ dispersion pattern is a figure 8; in the plane of the speaker little to no sound is sent to either side, which means Maggies can be placed closer to sidewalls than boxed speakers (although, even here, you need to be careful of energy being bounced from backwalls toward sidewalls and, thence, on to you).

One of the things Maggies do have issues with is power. You will need a good deal of it to drive them properly. An amp like the $2k 400Wpc (into 4 ohms) Parasound Halo A21 will do just fine.