Size: Driver's nominal size (manufacturer's rating)
Imp: Driver's nominal impedance (ohms)
Date: Date at which measurement was performed (driver specs may change from year to year as
improvements are made by the manufacturer
Re given in ohms, Vas in litres, Xm in mm, Sd in cm^2 and Pe in Watts.
For Dual Voice Coil (DVC) drivers, the Impedance given is the impedance of the two coils wired
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