The HD measurements at distance 315 mm and voltage levels 2.83 - 4 V were carried out with High Pass Filter (2nd order Butterworth type, 80 Hz cutoff, HPF2-80)
The HD measurements at distance 315 mm and voltage levels 5.6 - 11.2 V were carried out with High Pass Filter (2nd order Butterworth type, 100 Hz cutoff, HPF2-100)
The voice coil current HD measurements at voltage levels 2.83 - 5.6 V were carried out with High Pass Filter (2nd order Butterworth type, 80 Hz cutoff, HPF2-80)