Right, let’s get something clear from the outset. The MartinLogan Summit X is one of the best speakers on the market at this time. The combination of full-range performance, seamless integration between treble and bass and the fact that it doesn’t cost as much as a Gulfstream jet to buy or partner make it a package that’s hard to beat. It’s not a panacea and is demanding of both installation and room dynamic, and it won’t win over hardcore box lovers or die-hard Quadites, but for many it will give a performance you’d have to blow many tens of thousands more to get even close to.
As the name might suggest, the Summit X builds upon the strengths of the original Summit. The original Summit was praised for being one of the first electrostatic/cone hybrid designs to have finally and ultimately ‘nailed’ the integration between treble and bass. The same holds here… and then some.
On paper at least, the changes between the two are not that significant. It’s almost five centimetres taller and a couple deeper. It’s now single-wired, instead of bi-wired. It’s one decibel more sensitive, at a claimed 91dB/W/m, but a minimum impedance of 0.8ohms (admittedly at 20kHz) suggests it needs a good amp to drive it (we used a darTZeel CTH-8550). It’s also considerably more ‘green’, drawing less than one watt per channel in idle mode, compared to the 20W in the previous model. But there’s more than just the on-paper changes; between the Summit and the Summit X, the MartinLogan design team came up with the mighty CLX full-range electrostatic. A considerable amount of the R&D that went into that new range-topper went into adding that X-rated suffix to the Summit.
The curved 112mm tall XStat stator panel seen in the original Summit remains effectively unchanged, as does the aluminium AirFrame housing the stator panel sits in and the ClearSpar alloy spacers used to keep the assembly stiff (MartinLogan clearly loves its TradeNames). A very different crossover from the one in the Summit feeds this, and its here where the CLX development cycle shows its hand.
Once again, this is a Vojtko Voiced design (no special ingredients here; Joe Vojtko is the no-nonsense lead engineer at MartinLogan, who has been influential in producing some of the best products in the company’s history). However, this has been extensively reworked since the Summit. It still uses air-cored inductors and polypropylene capacitors, but the CLX taught the MartinLogan team that greater component matching and a heavily revised circuit topology (once again, a Joe Vojtko strong-point) brought even greater mid-band clarity.
Physically at least, the single biggest change is to the bass cabinet. As before, the Summit and Summit X notionally share the same dual 250mm aluminium drive unit bass module, powered by a 200W power amplifier. However, the Summit X now features ‘controlled dispersion’, adjusting phase as the bass approaches the crossover point. Below 100Hz, the two bass drivers are in phase, which helps enhance bass extension. Between 100Hz-160Hz, however, the bass units phase shifts to 180°. This effectively makes the bass act as a dipole, just like the main panel. There are also two bass adjustment controls at 25Hz and 50Hz.
Adjustment of the loudspeaker is limited to the spikes, or rather ETC (Energy Transfer Coupler) spikes. By mixing and matching the 75mm long spikes carefully, you can adjust the vertical angle of the speakers from 11° to -1°. This is incredibly important in getting the right sound for the listening position. Last, and entirely inconsequential to the sound, is a set of lights behind the logo, over the control panel and under (‘Ground Effect’) the speaker. Inconsequential, yes… but do add a lot to the overall appeal of the speaker. You can switch one or all off if you want. There are seven wood finishes and either black or silver metal work as standard and a Custom Shop for virtually any finish you can think of.
The manual suggests a unique way of installing the speakers. Begin with the speakers firing directly down the room and the front centre point of the speaker precisely 60cm from the rear and side walls. Then measure the distance between the two loudspeakers (X) and describe a triangle with the two speakers at the base and you sitting either at the vertex of an equilateral triangle (each line X cm long) or an isosceles triangle (with the base line X cm long and the other lines up to 2X cm long). Then, sitting in the hot seat, shine torchlight from under your chin (really) onto the MicroPerf stator front. The light should reflect back from the inner portion of the curved stator, not the centre or outside section. You can also then adjust the vertical angle using the ETC spike assembly, to make the reflected light. The closer you are to the speaker, the nearer you get to forward tilting. This is only the start; once you have run in the speaker, experiment with all this over again, and the manual has even more suggestions on this, too.
Running in is suggested at 72 hours played using real music programme at moderate listening levels (around 90dB). But that comes with some caveats, not in the manual. If you move the speakers or turn them off for any significant length of time… run them in again. Electrostatic panels are sensitive to movement and not being constantly energised, even at low powers. This means it’s hard to get an instant demonstration and dealers need several days notice to set them up.
It also takes a bit of time to get used to the sound of the Summit X after a life spent staring at ‘monkey coffins’. The sound is very laid-back and almost undynamic on first listen. Then, you begin to acclimatise, and acclimatise quickly. About three tracks will do the trick. What came across as laid back is the absence of tweeter beaming. That undynamic sound is in fact the lack of box coloration rumbling along with the music. Granted, if your musical collection is limited to the stretch between AC and DC and you dream in power chords, this will always sound somewhat flat to you, but those who are not afraid of unplugging the instruments are more swayed by the Summit X.
It’s strange; the Summit X both has and lacks the properties that sum up electrostatic loudspeakers perfectly. It has that big, effortless midrange and treble, but not with the sort of pin-sharp stereo soundstaging commonly found with big flat panels. Instead, what it sounds like is one dirty great big electrostatic panel stretched between the loudspeakers, albeit still retaining some of the point-source properties of other stator panels.
It’s not the last word in neutrality, with a distinct ‘enriching’ character to the sound, but this might not be a bad thing. Some will love its performance, citing how it enhances articulation and integration of sounds, especially in the midrange. Others will listen to the same and criticise it because of the word ‘enriching’ and ‘enhancement’. Whatever, it’s clearly a speaker that’s going to promote healthy debate. These speakers are all about musical flow, and that might even occur when ‘flow’ is not a word that sums up the music. Themes in a piece of music blend together with a sense of naturalness that could turn Stockhausen into Rachmaninov. And when it comes to Rachmaninov… Isle of the Dead becomes the ambient tone poem it so often fails to be in other systems.
There’s something particularly wonderful about the Summit X and voices. Especially voices recorded in a natural ambiance. One of my less played (or at least, less discussed) demo discs is Canticles of Ecstasy by Sequentia, a series of Hildegard of Bingen’s works played by a seven-piece female vocal group, accompanied by medieval harp and fiddle and released by Deutsche Harmonia Mundi back in 1994. I don’t play it that often because it so rarely works. But through this system, the effect is hypnotic in that kind of atavistic way that pre-modern music can – and should – behave like. Hairs raise on the back of your neck, you feel more spiritual and yet strangely keen to burn yet another unbeliever for daring to question Aristotle’s horse-tooth counting abilities. Or something.
In more modern music, John Mayer’s "I’m Gonna Find Another You" could have been composed for the Summit X, or vice versa. Its combination of blue-eyed 60s soul meets mellow Hendrix-esque guitars is neatly brought to the fore, in part because of the excellent articulation and instrument separation. It rates at least a four or even five ‘o’ smooth, too.
As mentioned earlier, the default criticism of MartinLogan speakers in general is the integration between bass cone and the stator panel. The bass driver can never keep up with the speed of the electrostatic panel, so the logic goes. In fairness, this criticism has its roots in ML designs of old, so it’s not without some grounding in reality. But it does not apply here at all. Take that old fave, "The New Cobweb Summer" by Lambchop; a mellow, laid back presentation underpinned by some extremely well-defined and deep bass. Everything kept time well, and the deep bass rumbled along nicely. Where the really big guns score over the Summit X is when the bass gets really deep and the speaker cannot differentiate those low pedal notes on an organ, for example. That being said, the "Holcane Attack" from Apocalypto moved some serious air in the opening sections.
This is perhaps why the Summit X has got itself a reputation for being the CLS-beater. Those with the older, full-range speaker from 20+ years ago still cling to the design because it was the first – and still by many standards, the best – do-it-all electrostatic. It did this by effectively bolstering up the panel with a deliberate 50Hz resonance, but the result was extremely effective. Although it had a few running changes and improvements, it took a couple of decades for the basic CLS design to be superseded by the CLX. Unfortunately for CLS owners, this was a bit of a double whammy, because MartinLogan began to come up with hybrid loudspeakers that also deliver the goods at the bottom end with no sign of problems elsewhere. The Summit X only adds to the CLS-owner’s pain. Sorry guys… the Summit X are a better package in every respect. Still, the fact it’s taken 20 years to come up with that conclusion shows just how good those original electrostatics were.
Despite hammering down the coffin lid on the CLS, no system is perfect and even the Summit X has its limits. In particular, it falls short in delivering the sort of grunt needed to make a CD remaster of the first Johnny Winter album sound more than just a mess of instruments. It’s almost as if there’s too much information being thrown at you and where on some systems, the two guitars at the edges of both channels work well together, here you attention switches from one to the other too fast. In fairness, this is a tough call at the best of times, because such recordings usually have none of the subtlety we normally crave in high-end.
However, this acts more as differential diagnosis, to highlight where the Summit X fits in the pantheon of high-end loudspeakery. As you might imagine, it fits snugly between the refined-but-undynamic sound of many electrostatic-only designs and the dynamic-but-boxy sound of cones and domes. For some, the True Path to high-end audio is the electrostatic speaker, but if you have spent years listening to boxes, the move to panels is too great a sonic change; the Summit X represents the no-compromise compromise between the two. In effect, it’s a gateway loudspeaker for that True Path, offering the dynamic range of boxes with the transparency of panels.
Especially in recessionary times, people are quick to jump on high-end audio as an expensive folly, irrespective of the stratospheric performance such products can deliver. In part, this is because they see prices that would make De Beers blush. Then there are products that also deliver stratospheric performance, but at a more manageable price point. The MartinLogan Summit X is one such product, delivering reference-grade performance that you’d struggle to match at double the price. This could spell the end of monkey coffins for many listeners.
Go hear now!
Type: Hybrid electrostatic/dynamic loudspeaker
Drive units: 1120mm curved electrostatic panel; 2x 254mm cast basket, high excursion, aluminum cone with extended throw drive assembly
Subwoofer type: integrated, nonresont asymmetrical chamber
Subwoofer power: 2x200 watts per channel (into four ohms)
Controls: boost/cut controls at 25 and 50Hz, accent light controls
Input: Single wired, custom binding posts
System Frequency Response: 24Hz - 23kHz ± 3db
Dispersion Horizontal: 30 Degrees
Vertical: (112 cm) line source
Impedance: Nominal 4ohms, Minimum 0.8 ohms at 20kHz
Crossover frequency: 270Hz
Power handling: 300w per channel
Mains power draw: Standby <1W/channel
Weight: 34kg per speaker
Dimensions (WxHxD): 32.2x154.8x54cm
Price: £12,998 (black, dark and natural cherry), £13,998 (all other finishes)