Transducer Size (Millimeters)165.1
DC Resistance3.43
Resonant Frequency39
Half Space Sensitivity90.52
Rated Noise Power50
Test Spectrum Bandwidth20Hz-20KHz

Transducer Size (Millimeters)165.1
DC Resistance3.43 Ω±5.0%
Resonant Frequency39 Hz15%
Half Space Sensitivity @ 2.83V90.52 dB±1.01
Sensitivity @ 1W/1m88.1 dB±1.01
Rated Noise Power (IEC 268-5 18.1)50 W
Test Spectrum Bandwidth20Hz-20KHz 12 dB/Oc
Effective Piston Area143.1 cm2
Moving Mass18 g
Motor Force Factor6.33 T•m
Voice Coil Inner Diameter32.41 mm
Gap Height6 mm
Maximum Linear Excursion5.1 mm
Ferrofluid Type
Minimum Impedance4.63 Ω±7.5%
Voice Coil Inductance0.19 mH
Mechanical Q Factor2.2
Electrical Q Factor0.38
Total Q Factor0.32
Ratio121.11 fs/Qts
Energy Bandwidth Product ((1/Qes)•fs)
Suspension Compliance924.4 μm/N
Effective Cone Diameter13.5 cm
Motor Efficiency Factor11.7 (T•m2)/Ω
Voice Coil Former MaterialASV
Transducer Mass1.58 Kg
Equivalent Volume26.6 L

This 4 ohm 6.5 inch 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 a paper cone, offering a unique visual and acoustic experience.