Acoustic Research AR IC Architectual Speakers In Wall / Ceiling 6.5 2 Way Pair. Acoustic Research IC65 6.5-Inch Ceiling Speakers, White; 6 1/2″ Polypropylene Woofer; 1″ Silk Dome Swivel Tweeter; Frequency Response: 40 Hz-25kHz +/- 3dB; Sensitivity: 89dB; System Impedance: 8 Ohms; White paintable finish.