Transducer Size (Millimeters)457.2
DC Resistance3.67
Resonant Frequency27.8
Half Space Sensitivity94.62
Rated Noise Power800
Test Spectrum Bandwidth40Hz ~400 Hz

Transducer Size (Millimeters)457.2
DC Resistance3.67 Ω±5.0%
Resonant Frequency27.8 Hz15%
Half Space Sensitivity @ 2.83V94.62 dB±1.01
Sensitivity @ 1W/1m91.9 dB±1.01
Rated Noise Power (IEC 268-5 18.1)800 W
Test Spectrum Bandwidth40Hz ~400 Hz 12 dB/Oc
Effective Piston Area1225.4 cm2
Moving Mass195.8 g
Motor Force Factor16.94 T•m
Voice Coil Inner Diameter75.7 mm
Gap Height10 mm
Maximum Linear Excursion12 mm
Ferrofluid Type
Minimum Impedance4.3 Ω±7.5%
Voice Coil Inductance1.05 mH
Mechanical Q Factor14.98
Electrical Q Factor0.44
Total Q Factor0.42
Ratio66.19 fs/Qts
Energy Bandwidth Product ((1/Qes)•fs)
Suspension Compliance0.2 μm/N
Effective Cone Diameter39.5 cm
Motor Efficiency Factor78.2 (T•m2)/Ω
Voice Coil Former MaterialTIL-P
Transducer Mass12.06 Kg
Equivalent Volume356 L

This 18 inch 4 ohm speaker features a FEA optimized ferrite magnet motor, 3inch voice coil, cloth surround, paper cone, a vented yoke for motor cooling, and a high strength stamped steel frame. Kevlar loaded non-pressed paper cone to help dampen and control cone resonance. The multi-roll surround and spider have been optimized to reduce distortion over the excursion range of this transducer.