Folded Motion™ Tweeter 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. Stealthy Grilles MartinLogan’s new 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. S P E C I F I C A T I O N S Frequency Response 47–25kHz ±3dB Horizontal Dispersion 80° Vertical Dispersion 80° Sensitivity 90 dB/2.83 volts/meter Nominal Impendance 4 Ohms. Compatible with 4, 6 or 8 ohm rated amplifiers. Recommended Amplifier Power 20-200 watts per channel Crossover Frequency 2,500 Hz High Frequency Transducer 1” x 1.4” (2.6cm x 3.6cm) Folded Motion Transducer with 5.25” x 1.75” (13.3cm x 4.4cm) diaphragm. Low Frequency Driver 6.5” (16.5cm) aluminum cone with cast aluminum basket. Concave dust cap. Weight 5.5lbs. (2.5kg) each Overall Dimensions 11” (27.9cm) Height 8.5” (21.6cm) Width 3.925” (10cm) Depth Cut-Out Dimensions 10.25” (26cm) Height 7.875” (20cm) Width Depth Required Behind Wall Surface 3.8” (9.7cm) Projection From Wall Surface .125” (.3cm)