The HD measurements at voltage levels 2 - 11.2 V were carried out with High Pass Filter "on" (2nd order Butterworth type, 800 Hz cutoff, HPF2-800)
The voice coil current HD measurements at voltage levels 2.83 - 8 Volt were carried out with High Pass Filter "on" (2nd order Butterworth type, 800 Hz cutoff, HPF2-800)