MAGNEPAN 30.7 FOUR-PANEL DIPOLAR PLANAR LOUDSPEAKER SYSTEM

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1 MAGNEPAN 30.7 FOUR-PANEL DIPOLAR PLANAR LOUDSPEAKER SYSTEM By Chris Martens Jun 25, 2018 Products: Magnepan 30.7 Equipment+ The White Bear Lake, Minnesota-based loudspeaker manufacturer Magnepan never takes the launch of a new flagship model lightly and this is especially true in the case of the recently released four-panel 30.7 dipolar loudspeaker system ($30,000/pair in the US). For readers who have never seen Magnepan loudspeakers in the flesh, it helps to know that they are tall, wide, thin, and completely boxless dipolar, panel-type speakers that look much like tasteful room divider screens. I have long used Magnepan speakers in my reference system and to be candid visitors who see the Maggies for the first time often find it difficult to believe they even are loudspeakers (as in, Riiight, they re loudspeakers if you say so now what are they really? ). After a few well-chosen musical tracks, however, disbelief typically turns into the good kind of shock and awe. My point: Magnepans don t look like typical box speakers and don t sound like them either.

2 For more than a decade, Magnepan s models geared for two-channel applications have used a single, multi-driver speaker panel per channel. In earlier years, however, Magnepan offered top models such as its Tympani-series speakers (culminating in the famous Tympani IVa) that employed three vertically orientated panels per channel. In fact, the largest variant of the Tympani (the Tympani IIIa) used an astonishing total of eight panels (two tweeter/midrange panels on the left, another two on the right, and four bass panels in the middle), which meant that in most rooms it was a literal wall-to-wall loudspeaker. While undeniably legendary in their day, the Tympani models required very careful set-up and equally careful selection of ancillary components in order to sound their best. What is more, they took up so much space that they probably set records for generating spouse acceptance problems ( Look dear, you can t seriously be planning to put those things in our lounge; not now and not ever. ). Even so, the sound of the late, lamented Tympani s was so compelling, so realistic, and so unforgettable that enthusiasts have been pestering Magnepan ever since to create a modern-day Tympani equivalent, but updated with 21st century materials and technologies. This is precisely where the model 30.7 comes in. The 30.7 is by far the highest performance loudspeaker Magnepan has ever made and though it is a large speaker, it seems visually more compact than the original Tympanis. Nevertheless, through extremely space efficient design the 30.7 s manage to offer fully 22% more driver surface area than did the Tympani IVa. Each 30.7 speaker consists of a large bass/lower-midrange panel and a considerably narrower midrange/tweeter panel, where the tweeter/midrange panel is designed to stand beside and a little behind its companion bass panel (this in order to achieve proper time alignment). Like most Magnepan speakers, the 30.7 s are built in mirror-image pairs, thus giving users numerous set-up options through which panels can be positioned to optimise greater imaging focus and specificity, broader and deeper soundstages, or in the best cases both. The 30.7 model is so new that Magnepan has not yet published the new model s manual nor finalised its specifications, but through discussions with Wendell Diller, Magnepan s head of Marketing and Sales. I was able to learn much about the design. The 30.7 s large bass/lowermidrange panel, says Diller, is the same size as Magnepan s 20.7 loudspeaker (that is, inches or cm H W D). The tweeter/midrange panel, in turn, is the same height and depth as the bass/lower-midrange panel, but a bit more half the width (it is 16 inches or 36.8 cm wide). Importantly, the 30.7 is Magnepan s first-ever four-way speaker. The woofer/lowermidrange panel uses two differently sized rectangular ribbon-type planar bass drivers an arrangement that means the two bass drivers have different diaphragm resonances thus yielding a smoother response curve overall. The smaller bass driver features along its outward facing side an also rectangular quasi-ribbon-type transitional linesource driver that covers lower midrange frequencies. Interestingly, the smaller bass driver and the lower-midrange line-source driver share a common diaphragm membrane, but use entirely separate voice coils, each optimised for its assigned frequency range. The drivers in the bass/lower-midrange panel use front and rear magnet arrays, just as do the drivers in the 20.7 loudspeaker a design touch said to increase efficiency while minimising distortion.

3 The tweeter/midrange panel features Magnepan s signature pure-ribbon linear tweeter widely regarded as one of the finest high frequency transducers in the world. The tweeter is positioned alongside a tall and relatively narrow ribbon-type planar midrange driver that introduces an all-new, proprietary, and ultra-low mass diaphragm material, which Diller says helps to make this by far the fastest and most responsive midrange driver Magnepan has ever produced. The midrange driver, like the other quasi-ribbon drivers in the speaker, uses front and rear magnet arrays. First order (6dB per octave) crossover networks are used throughout, with part of the network built into the bottom of the bass/lower-midrange panel and part built into the bottom of the midrange/tweeter panel. By dividing its workload between four groups of drivers a set of two planar woofers, a transitional line source lower-midrange driver, an extremely low-mass midrange driver, and a pure ribbon tweeter the 30.7 aims, says Diller, to provide lower mass (vs. frequency), better power response, and better bass than any previous Magnepan design. It is also the most adjustable Magnepan ever, in that it allows separate adjustment of lower-midrange, midrange, and tweeter driver output levels and also positioning adjustments between the bass/lower-midrange panel and the midrange/tweeter panel. The good news is that the 30.7 can be made to work well in a surprisingly large variety of rooms (and to fit a broad range of listener tastes), but please note that it may take a significant time, patience, and experimentation to achieve optimal sonic results. For this reason, Magnepan requires all dealers wishing to sell the 30.7 to commit to providing the painstaking set-up and adjustment services the speaker needs and deserves.

4 What I hope to provide here is not so much a definitive loudspeaker review of the 30.7, but rather a preliminary assessment of its performance potential. With this goal in mind, I accepted an invitation from Magnepan to audition the speaker in the firm s Minnesotabased sound room/development lab. During my listening session we drove the 30.7 s with an Audio Research Corporation CD6 CD player/dac, an ARC Reference 6 preamplifier, and a pair of ARC Reference 250 valve-powered monoblock amplifiers, with entry-level Kubala-Sosna cables used. For part of the session, however, we removed the Ref 250 monoblock amps and substituted the power amplifier section of a prototype, third-party solid-state stereo integrated amplifier, mostly to see how the speakers would respond to solid-state amplification. Beforehand, Diller positioned the 30.7 panels for ideal (and empirically verified) time alignment. In practice this meant all the panels were toed in toward the listening position, with the bass/lower-midrange panels placed near the sidewalls of the room and with the tweeter/midrange panels placed inward from the bass/lower-midrange panels and roughly six inches behind them. During the session, Diller and I made several small (yet cumulatively significant) adjustments to the various driver output levels, which helped the speaker to achieve increasingly more neutral tonal balance throughout the room. A subsequent pink noise test revealed that our efforts were largely successful, though Diller and I felt that, given more time for fine adjustments and selective application of room treatments, we perhaps could have improved further still on the speakers already superb sound.

5 My first finding was that the 30.7s are well and truly full-range loudspeakers with all the top and low-end extension one could possibly want. Many audio mavens think big dipolar speakers are incapable of producing authoritative bass reaching down into the 20 Hz range, but the 30.7s quickly dispel that notion by displaying an admirable mix of low-frequency extension, power, transient speed, and impact. These qualities were much in evidence both on recordings highlighting acoustic and electric bass instruments for example, the subtle low frequency pipe organ modulations captured in the Tilson Thomas/San Francisco Symphony recording of the Copland Organ Symphony [SFS Media, 16/44.1] or the sharp, percussive bark of Stanley Clarke, Marcus Miller, and Victor Wooten s electric bass guitars as heard on the Lopsy Lu Silly Putty medley from S.M.V s Thunder[Heads Up, 16/44.1]. Particularly on the latter track, the 30.7 s bass clarity, snap, and punch rivalled (or surpassed) that of far more costly dynamic driver-type loudspeakers. Next, I was struck by the terrific openness, transparency, and focus of the 30.7s, from the lower midrange right on up to the highest treble frequencies. Stated simply, this speaker is a master of textural nuance, transient acuity, and dynamic expression. Through the Maggies, then, I found myself getting delightfully caught up (and then lost) in the delicate, expressive inflections of Lyn Stanley s voice on My Funny Valentine from the singer s The Moonlight Sessions, Volume One[A.T. Music, 16/44.1]. Similarly, I was inexorably drawn into the variegated timbres and modes of attack as heard from trumpeter John Adler and pianist Tracy Cowden s respective instruments on the title track of Adler s Confronting Inertia[Origin Classical, 16/44.1] a track that showcases many different trumpet and piano moods ranging from whisper-quiet musical comments to bold, powerful, and dynamically dramatic statements. Two qualities that impressed me throughout were the 30.7 s effortless sense of ultra-fine resolution and superabundant transient speed from top to bottom. It s in these areas where the 30.7 proved itself not only to be the best Magnepan ever, but one of the finest loudspeakers available at any price. Third, I was won over by the 30.7 s remarkable to convey sonic images and soundstages that are remarkably realistic in size and scale. This is a performance parameter where the 30.7 s handily outperform all but the largest, most capable, and typically most expensive dynamic driver-type loudspeakers. Part of this results from the 30.7s uncommonly good power response throughout the listening space something I was able to verify by walking around the listening space while observing the remarkable smoothness and evenness of the Maggies overall sound across multiple locations. Part is also attributable to the speaker s sheer size; these are large, dipolar, linear array speakers whose drivers produce sound everywhere from a few inches to more than six feet above floor level. The result is a speaker that can produce realistically (but not exaggeratedly) tall, broad, and deep soundstages with a just-right degree of imaging specificity and focus. To appreciate what I mean, listen to the 30.7 s rendition of Aphrodite from Robert Paterson s The Book of Goddesses [America Modern Recordings, 16/44.1], which shows the Maya ensemble s distinctive combination of flute, harp, and percussion instruments performing in a richly reverberant recording space. Through the Maggies, the instruments sound realistic (in timbre, dynamics, and overall scale) and so too does

6 the space; it s a true three-dimensional treat. Another great example would be the Jamey Haddad, Lenny White, and Mark Sherman percussion trio s performance of the vibrant and intensely syncopated track Stank from Explorations in Space and Time[Chesky, 16/44.1]. In this case, the listener hears the interplay of three master percussionists performing on a wide array of instruments as recorded in the interior of a church. The 30.7 renders each of the instruments voices with impressive purity and realism, but it s the interaction of those voices with the acoustics of the church that invites the listener to suspend disbelief and be transported to the time and place where the recording was made. In practical terms, 30.7 ownership does entail a few caveats. First, the four-panel speaker is comparatively wide and will not fit in every room. Note, however, that it is possible to place the bass/lower-midrange panels directly against the sidewalls of the room with no adverse effects, meaning this speaker system could conceivably be used in rooms as narrow as about 13.5 feet in width. Second, the speaker requires careful set-up and adjustment in most rooms in order to sound its best. This isn t a simple set it and forget it design; instead, it takes time and patience to tease out its highest levels of performance. Third, this is a speaker that sounds best from a single, central listening position; move from that and the speaker s uncanny threedimensionality and imaging focus will fall off considerably. But sit in the middle seat and you will find your self in the centre of the sonic promised land. Magnepan s 30.7 is in my view a landmark design one that does all things well and some things (textural and transient nuances, three-dimensionality, and realistic image scale) extraordinarily well. While $30,000 is a lot to pay for any pair of loudspeakers, the fact is that the 30.7s deliver sound quality competitive with (and in some respects superior to) loudspeakers ranging from two to nearly ten times their price. This means the 30.7 is at once an expensive product that also offers exceptional value for money! If you have the chance, I urge you to hear Magnepan s 30.7, if only to experience what a world-class $30,000 loudspeaker system can really do. TECHNICAL SPECIFICATIONS Type: Four-way, four-panel, quasi-ribbon/pure-ribbon dipolar planar loudspeaker (each speaker includes a large bass/lower-midrange panel and a smaller midrange/tweeter panel) Driver complement (per speaker): two quasi-ribbon bass drivers, one quasi-ribbon transitional line source lower-midrange driver, one quasi-ribbon midrange driver with ultralow-mass diaphragm, and one pure-ribbon high frequency driver. Frequency response: 20Hz 40kHz Impedance: 4 Ohms Dimensions (H W D): cm, bass/lower-midrange panel; x 36.8 x 5.2 cm, midrange/tweeter panel Finishes: Frame: Wood: Natural or black solid oak, dark cherry Aluminium: Silver, Black, Red, or Blue. Fabric: Off-white, black, and dark grey Price: $30,000/pair in the US; UK and EU prices were not yet established as of this writing Manufacturer: Magnepan Incorporated