February 2006

MartinLogan Summit Loudspeaker
Hoping they can finally mix panels and drivers properly.
Review By Alvin Gold
Click here to e-mail reviewer

  The Summit made its first appearance behind closed doors to a trade only audience at the 2005 CES show in Las Vegas. Nominally the Summit is billed as the replacement for the Odyssey and the Prodigy, but in effect it is the new flagship of the range. What we were not told at the time, and discovered only much later in the year, is that the Summit was the swan song for MartinLogan's prime mover and shaker, Gayle Sanders, who chose 2005 to relinquish day to day control of the company. My personal regret is that he will not deliver on his promise made in an interview a couple of years ago that there would be a true replacement for the CLSIIz single driver, full range electrostatic, and in many ways MartinLogan's seminal product. But let's not get too doe-eyed about this. The CLS in its various iterations was always flawed, and in the real world you couldn't wish for a better swan song than the Summit.

If you only take four words from the introductory paragraph above, let it be 'in the real world'. If you understand that, you will understand the essence of this remarkable speaker. In a way, the story of MartinLogan from the outset has been a continuing struggle to produce hybrid electrostatic speakers that are progressively more practical and seamless. Along with most other electrostatic producers (with the obvious exception of Quad), their chosen means has been the hybrid loudspeaker, which uses a moving coil bass section to supplement an electrostatic panel that covers the midrange and treble. All MartinLogan loudspeakers subsequent to the CLS have been hybrids, with the electrostatic panel left to cover the range above 300Hz or so, but they have periodically changed the recipe. MartinLogan has also pioneered the use of panels which are curved in the horizontal plane and most shocking of all to the purist, supplementary moving coil tweeters to widen the vertical imaging of some of their designs. You may already know that the company makes some ground breaking subwoofers, led by the aptly named Descent.

In a way, nothing has changed with the Summit, which at first sight is just another two-way floor standing hybrid, albeit with some intriguing variations in detail. But as those who have heard it will know, much has changed. The first real surprise for those privy to the CES 2005 demonstrations was that it is relatively small and compact, a surprisingly slender and unobtrusive design, the result of separate slimming down exercises aimed at reducing the bulk of the electrostatic panel and of the bass section. It was also designed to sell for significantly less than its predecessors.

Electrostatic panels are not easy to shrink unless you're willing to sacrifice loudness capability or bandwidth, and both were ruled out for the Summit. Bandwidth and loudness are intimately related to physical size, and if performance is not to be reduced, its size must be retained. Nevertheless valuable inches have been shaved off the panel, not by shrinking the panel itself, but by redesigning its termination, the frame that supports it. Where older MartinLogan designs used large wood frames for their ELS panels, the Summit uses a thin square section aluminum tube for the two vertical sides, stiffened by an internal threaded truss rod, which is torqued to the point where it maximizes rigidity. The top section look identical, but in fact is a solid milled aluminum billet. Compared to the older wood door frame like construction, the new design is smaller overall, but it has the same sound generating area as the Prodigy, a much bigger loudspeaker that has been replaced by the Summit, and it is 1dB more efficient while offering some claimed sonic advantages, specifically better dynamics, some bandwidth improvements and greater transparency. But these are claims rather than proven fact, and we'll come back to these points in due course.

Changes to the bass section are more radical. Previous MartinLogans have used passive bass sections, most recently using two bass drivers, one rear facing the other at the front, in an attempt to control directivity. This time MartinLogan has taken its cue from subwoofer technology by ditching its traditionally inspired bass section in favor of a self powered system with active equalization - a subwoofer in fact, which operates south of 270Hz. The Summit employs a pair of 10 inch alloy cone long excursion drivers of proprietary design, one downwards facing, one at the front, powered by two internal 200 Watt amplifiers per loudspeaker (that is four amplifiers for a total of 800 Watts per pair). The Summit bass section uses a relatively compact enclosure, in keeping with the designer's intention of shrinking the loudspeaker, and this is achieved using active equalization, that is boosting the lowest frequencies electrically. The Summit also includes a pair of controls, to help independently fine tune the low frequency output, which operate like tone controls, one of which is centered on 50Hz (officially 40Hz to 60Hz +/-10dB), and the other on 25Hz (20Hz to 30Hz +/-10dB). But like all such networks there is considerable overlap, and the two settings should be considered as a rudimentary room EQ, with the ability to apply different settings per speaker to help cater for asymmetric room listening conditions.

Although all such bass systems are resonant to some extent, the Summit subwoofer section is comparatively non-resonant compared to passive systems. There is no reflex port or duct for example, and the electronic equalization is fairly low Q (dependent to an extent on the settings of the controls). Visually the Summit clearly has a much smaller bass enclosure than previous designs - by as much as 75 percent according to the maker, or as he puts it, not much larger than a case of wine. But it delivers serious bass, which extends to 24Hz (-3dB).

The Summit's active amplification includes toroidal power transformers, as part of a high performance bipolar amplifier that is said to offer better tracking of the input signal and reduced hysteresis. Other claimed benefits are a more open, dynamic performance than would have been expected with otherwise similar IE transformers, especially at high levels. In general terms, bass performance comes closer than previous designs to matching the speed and transparency of the electrostatic mid and treble. The hard built crossover is derived from the network used in the Statement, with air core inductors, audiophile grade polypropylene caps and point-to-point hard wiring.

Sound Quality
Once again, let me repeat the standard health warning: the preceding performance related comments are the maker's claims, and they should be taken with the usual half-gallon of salt. But it turns out there is some correlation with the Summit's real life performance. It's not just that the Summit sounds good on paper and in practice, but that there are some specific elements to the sound of the Summit that correlate with the physical description

Let us start with a backwards look at the traditional MartinLogan house sound prior to the Summit, remembering here that we're taking generalities rather than about specific models. I did have an interesting gates of Damascus experience with one MartinLogan design (not one of their best), that is used as one of the test models in the Harman group blind listening facility which I was heard about 18 months ago. Of all the loudspeakers they used, the MartinLogan was clearly the most obvious and colored, and although there are good reasons why a panel speaker would probably not be done any favors in such an environment, I would accept that their speakers have never been the most neutral.

There are some quite complex colorations artifacts, not necessarily severe in character, but certainly noticeable enough, in the mid to upper midband, and a lack of the solidity you tend to get from the better box type speakers, though there are grounds for suggesting that their obviousness is partly related to the fact that we more often hear box loudspeakers and tend to learn to ignore their particular coloration signatures. At the same time there has always a certain magic to a good MartinLogan speaker which exists in spite of the sometimes over characterful tonal quality. There is a translucency, an at best exquisite sense of detail that shines through. Describing another (much les costly) MartinLogan model some time ago, for example, I wrote that "(it) lacks the almost electric sense and dynamism that is available from larger designs. Conversely however it is an extremely agile and transparent loudspeaker, which responds easily and fully to the varying tumbrel demands of different types of music. In Beethoven Opus 111, while it may not have quite the muscle to fully display the extraordinary architecture and statue of the music, the very distinctive metallic ringing quality and attack of the Steinway grand used in the test recording was captured beautifully, as was the subtle modulation of dynamics in the more restrained second movement."

The Summit came as quite a shock. It is cleaner, lower in coloration and somehow more together than previous models from this marque. The overall effect is sharper and leaner, and timing cues are more secure. The bass sounded very well sorted under the manufacturer's own conditions at CES, but when the speaker arrived for test, the default settings clearly sounded overcooked in my room, and some judicious tweaking, mostly involving adjustments to the 25Hz and 50Hz pots, was needed to effect a cure. The instruction manual contains a wealth of useful detail advice on setup.

It is hard to say whether the improvements identified over previous models stems from the moving coil bass or the electrostatic treble. Clearly there are improvements in both areas. But perhaps the biggest difference is the way the two end of the spectrum work together. There has always been more than a hint that the two end of the audio frequency spectrum in a MartinLogan did their own things, and although recent design are much more homogenous then older ones, they still seemed to have their own characteristic voicing, and different dispersion patterns, though the crossover area itself has long been practically seamless. The Summit is the first MartinLogan hybrid in which everything appears to come together. Finally, the bass has the sharpness, precision and speed that have long attended the midband and the treble, and overall this speaker sounds coherent and together in a quite new way. The bass is deep and powerful too, which has not always been the case with MartinLogan loudspeakers, but above all this is a tuneful, precise and low distortion bass that just happens to have palpable shape and substance too.

Old habits die hard. This is still not the speaker for you if you spend your time with manufactured pop, where the effect can be too revealing and up front, or heavy duty Marc Cohn style driving rock where the Summit lacks what s colloquially known as balls. But its balance is near ideal for virtually any kind of acoustic material, be it vocal (Suzannah McCorkle's sultry and beautifully nuanced SACD From Bessie to Brazil on Concord Jazz featured heavily in this test), chamber or orchestral, and quite irrespective of genre. I was surprised how well developed large scale Mahlerian orchestra textures were reproduced by the Summit, with the articulation of a very small speaker, combined with the dynamic, space and scale of a full size model.

There is a caveat here. The Summit could never be accused of being an easily load. Sensitivity is 92dB/W/m, which implies that not much power is required, and nominal impedance is 4 Ohms, but at high frequencies the impedance curve drops down to 0.7 Ohms at 20kHz, which requires an amplifier with certain self-discipline. A Krell KAV-280p and a KAV2250 pre and power amp for this test worked well here, and for its transparency and speed, a loudspeaker cable like Nordost's Valhalla really comes into its own. But the Summit is also more than usually responsive to the source — the music of course, but also the player. This is a speaker that has the ready analysis of a pair of fine headphones and it won't suffer shortcomings gladly. It readily conveyed the world of differences between a Teac Esoteric X-01 SACD player and what by normal standards is a more than routinely fine counterpart from Sony, the SACD 9000, which sounded smeared and opaque by comparison, differences which moving coil speakers generally tend to downplay.

Conclusions
The Summit represents a new paradigm for MartinLogan. It is much smaller than its predecessors and less expensive too, but it has a broader bandwidth and a superior loudness capability (by a relatively small but unmistakable margin. It has a more consistently expressive, more fine grain and homogenous sound. It is a classic win-win situation as long as you have the room to let them breath, and as long as your musical interests are largely acoustic. Rockers and those who enjoy dance music most certainly may want to look elsewhere. Also, you should be willing to purchase amplification that can handle their very challenging load requirements. 

Specifications
Type: Panel loudspeaker with self-powered dynamic driver woofer

Frequency Response: 24Hz to 23kHz (±3dB)

Horizontal Dispersion: 30 degrees

Vertical Dispersion: 44-inch line source

Sensitivity: 92dB/W/m

Impedance: 4 ohms nominal, minimum 0.7 Ohms @ 20kHz

Crossover Frequency: 270Hz

Woofer: Two 10-inch high excursion aluminum cone

Power Handling: 100 to 300 Watts per channel

Weight: 75 lbs. each

Dimensions: 12.3  x 20.5  x 59 (WxDxH in inches)

Price: $9,995 basic on up depending on finish/trim

Company Information
MartinLogan
2101 Delaware Street
Lawrence, KS 66046

Voice: (785) 749-0133
Fax: (785) 749-5320
Website: www.martinlogan.com