Martin Logan Expression ESL 13A Loudspeakers

Achieving the Laboratory Standard in Your Own Room

In the lab, MartinLogan engineers strive for transparency. Outside the lab, there’s one wildcard our engineers can never account for: Your listening room. The unique size and shape of your listening space (and the size and shape of its contents) can make bass waves do unpredictable things, greatly affecting a speaker’s overall performance.

The Expression ESL 13A integrates exclusive Anthem Room Correction (ARC) technology. By engaging ARC to control the low-frequency curve in relation to the output of the ESL panel (as seen in this graph), you will experience performance on par with MartinLogan’s audio test lab.

ARC measures low-frequency sound output in your room and compares it to optimal response curves that account for spatial anomalies. The advanced algorithms of ARC then effectively remove the anomalies, leaving only the ideal standard: realistically blended, natural-sounding bass performance in your listening space.

By minimizing room interactions with PoweredForce Forward bass technology and the advanced room correction capabilities of ARC, along with its unique synthesis of the ESL and bass sections, the Expression ESL 13A produces perfectly-etched imaging and focus; optimum natural reproduction of sound at lifelike listening levels; and agile, full-range operation in open air.

Clearly, it is this level of ultimate performance that separates the merely excellent from a true masterpiece.

New Ultra-Rigid AirFrame Blade Design

Expression ESL 13A XStat panels are joined to their speaker cabinets using MartinLogan’s redesigned AirFrame Blade construction, precision manufactured from an aerospace-grade extruded aluminum alloy. This material, and this exclusive manufacturing process, makes the panels extremely rigid.

The bold, forward-moving styling of this AirFrame Blade rail system, narrow and strong in front, broad and forceful from the side, is a modern design statement. It never obstructs playable surface area or interferes with the panel’s dipole sound radiation pattern. It also provides electrical and acoustical isolation, minimizing intermodulation distortion caused by vibration and resonance. The flowing lines emphasize the groundbreaking integration of the panel itself with the compact woofer and amplifier section. The breathtaking AirFrame Blade design enhances imaging, low-level sonic detail, accuracy, and speaker efficiency.

Curvilinear Line Source (CLS) Electrostatic Panel

CLS technology is an essential ingredient of every electrostatic loudspeaker we produce. Through our proprietary manufacturing method, we have built-in the panel’s gentle horizontal curvature. This unique design enhances the high frequency detail produced by the large radiating surface, without compromising overall sound quality. Notice how the gentle modern curve and perforation pattern gives way to the flat grille of the woofer section.

Controlled Dispersion Sound Radiation

The sound we hear from a loudspeaker is a combination of direct radiation from it to our ears, and reflections off of room surfaces—walls, floor, and ceiling. How our brains integrate this information is far from simple. Depending on the angle of incidence to the ears and the arrival-time difference between direct and reflected sound, reflections can either blur detail and stereo imaging, or enhance the natural impression of depth and openness.

Electrostatic panels, which are true dipole speakers, produce a nearly-ideal controlled dispersion radiation pattern. They send very little sound to the sides, thereby minimizing side-wall reflections, whose short arrival times tend to interfere with the perception of the direct sound. Their strong rear radiation, however, produces a generous amount of natural, ambience-enriching later-arriving mid- and upper register information.

New  PoweredForce Forward^™ Bass Technology