The ElectroMotion IW is a premium high-performance in-wall speaker that uses a 6.5 inch aluminum cone woofer and Folded Motion tweeter.
 
Folded Motion Tweeters
MartinLogan's exquisite Folded Motion tweeter boasts a radiating surface 8-times larger than a typical 1" dome tweeter.  The Folded Motion Tweeter works by moving air (which creates sound) perpendicular to the folded ridges of the diaphragm, similar to how an accordion works.  
 
This extremely low mass diaphragm "squeezes" air and requires almost 90% less excursion than the typical 1" dome tweeter, which drastically minimizes distortion while providing a lightning fast response time.  The increased surface area also provides a wide, yet controlled sound dispersion to create a realistic and carefully etched sound stage.  
 
Installer Friendly 
A robust mounting-lock system allows quick, trouble-free installation.  When not in use, the constant-control mounting locks are held securely within a self-contained housing.  When moved into place during installation, they couple the speaker's chassis firmly to the ceiling.  And if the speaker is ever removed, the locks retract and latch themselves back in their housings.
 
Stealthy Grilles 
ElectroMotion architectural speakers feature ultra-low profile, paintable micro perforated grilles with no visible bezel for near invisible integration into any wall or ceiling. A magnetic system secures grilles easily into place, reducing the risk of warping or damage during installation.