Transducer Size (Millimeters)101.6
DC Resistance5.17
Resonant Frequency91.08
Half Space Sensitivity85.87
Rated Noise Power25
Test Spectrum Bandwidth90Hz - 6kHz

Transducer Size (Millimeters)101.6
DC Resistance5.17 Ω±5.0%
Resonant Frequency91.08 Hz15%
Half Space Sensitivity @ 2.83V85.87 dB±1.01
Sensitivity @ 1W/1m84.4 dB±1.01
Rated Noise Power (IEC 268-5 18.1)25 W
Test Spectrum Bandwidth90Hz - 6kHz 12 dB/Oc
Effective Piston Area56.8 cm2
Moving Mass6.1 g
Motor Force Factor4.94 T•m
Voice Coil Inner Diameter25.73 mm
Gap Height6 mm
Maximum Linear Excursion3 mm
Ferrofluid Type
Minimum Impedance5.72 Ω±7.5%
Voice Coil Inductance0.16 mH
Mechanical Q Factor1.92
Electrical Q Factor0.74
Total Q Factor0.53
Ratio171.85 fs/Qts
Energy Bandwidth Product ((1/Qes)•fs)
Suspension Compliance504.8 μm/N
Effective Cone Diameter8.5 cm
Motor Efficiency Factor4.7 (T•m2)/Ω
Voice Coil Former MaterialASV
Transducer Mass0.92 Kg
Equivalent Volume2.28 L

This 4 inch 8 ohm driver is a member of the high performance HDS family. A powerful ferrite magnet system is coupled to a finite element analysis designed suspension system, containing both a linear spider design and a rubber surround. The motor contains an aluminium shorting ring, which reduces coil inductance, thus providing both extended frequency response performance and reduced distortion. The long-throw voice coil ensures linear high excursion performance, needed for signal clarity. The cone necks are vented so as to reduce air compression effects under high excursion conditions. The cast aluminium basket offers structural rigidity, heat sinking capacity for the motor, and additional air venting under the spider so as to again reduce air compression effects. The cone in this model is damped black polypropylene, offering a unique visual and acoustic experience.