Lowther PM4 Drive Unit
PM4A Drive UnitPM4 Drive Unit
DC Resistance of Voice Coil Re 7.4 ohms
Free Air Resonance Fo 45 Hz
Emission Piston Area Sd 0.021M²
Equivalent Volume Suspension Vas 60.489 Ltrs
Suspension Compliance Cms 965.934 u M/N
Mass of Cone Mmd 11.0 g
Mass of Moving Parts Mms 12.75 g
Force Factor Bl 12.511 T-M
Mechanical Q Factor Qms 3.75
Electrical Q Factor Qes 0.172
Total Q Factor Qts 0.164
Voice Coil Inductance @ 1 kHz Le 23.178 uH
Reference Efficiency No 3.176%
Sound Pressure Level SPL 97.038 Db