How ultrasonic cavitation works what does ultrasonic actually mean ultrasonic refers to sound frequency an ultrasonic cavitation handpiece will make a sound we cannot hear while it is vibrating we measure the vibration times per second as sound frequency and refer to this as hertz humans can hear from 20 hertz to 20 000 hertz we are unable to hear anything above or below these levels therefore soundwaves with frequency above 20 000 hertz we call ultrasonic a megahertz is 1 000 000 he