The THD measurements at distance of 315 mm and voltage level 2.83 Volt were carried out with High Pass Filter "on" (2nd order Buttreworth type, 100 Hz cutoff, HPF2-100)
The THD measurements at distance of 315 mm and voltage levels from 4 Volt to 5.6 Volt were carried out with High Pass Filter "on" (2nd order Buttreworth type, 150 Hz cutoff, HPF2-150)
The THD measurements at distance of 315 mm and voltage level 8 Volt were carried out with High Pass Filter "on" (2nd order Buttreworth type, 200 Hz cutoff, HPF2-200)