Consisting of a 165 mm (6.5") Tannoy Dual Concentric™ point source, constant directivity drive unit with an additional 25 mm (1") Tannoy SuperTweeter™, the full bandwidth iw6 TDC is designed primarily for installation into standard stud partition wall systems, and may also be used in cavity wall installations constructed with standard thickness drywall as well as a wide range of other wall construction types with a surface thicknes of up to 25 mm (1”). Frequency Response (-3 dB): 75 Hz - 51 kHz. System Sensitivity (1 W @ 1 m): 91 dB (1 W = 2.83 V for 8 Ohms). Nominal Coverage Angle: 90 degrees conical. Transformer Taps (optional) 70 V: 60 W / 30 W / 15 W / 7.5 W / OFF & low impedance operation - 100 V: 60 W / 30 W / 15 W / OFF & low impedance operation. Power Handling: Average: 90 W, Programme: 180 W, Peak: 360 W. Recommended Amplifier Power: 180 W @ 8 Ohms. Hole Cutout: 271.5 x 168.5 mm (10.70 x 6.63"). Maximum wall thickness - 25 mm (1.00"). Dimensions (H x W x D) Front Baffle: 320 x 209 mm (12.60 x 8.25"), Front of baffle to rear of magnet assembly: 104 mm (4.10"), Front of wall to rear of magnet assembly: 99 mm (3.90"). Net Weight (ea) 3.0 kg (6.6 lbs). Colour white (Ral 9016)