Martin Logan Expression ESL 13A

The Martin Logan Expression ESL 13A is a hybrid floorstanding speaker that combines a large electrostatic panel with an amplified active bass module. It belongs to the Expression range, positioned below the Renaissance ESL 15A, and features an architecture radically revised compared to the manufacturer's previous generations.

The heart of the speaker relies on a curved electrostatic panel (CLS technology) 33 cm wide, mounted on an ultra-rigid structure called AirFrame Blade. This panel handles the reproduction of midrange and treble frequencies according to the electrostatic dipole principle, while the bass is handled by a separate active module.

This bass module, called PoweredForce, houses two 25 cm diameter aluminium-cone woofers per speaker, housed in a compact enclosure. Each woofer is driven by its own 300 watt class D amplifier, giving two amplifiers per speaker. The whole system is managed by a 24-bit Vojtko digital filter, which incorporates a room acoustic correction system called ARC. An ARC 180 correction kit is available as an option to make use of this function.

This type of speaker is intended for a high-end hi-fi or home cinema system, in a dedicated listening room, where one seeks the transparency and precision typical of electrostatic designs while retaining the impact and low-frequency extension of an amplified active bass system. Installation requires sufficient space around the speakers, as the panel's dipolar radiation is sensitive to proximity to walls.