An aspiration system to control vacuum pressure in an ultrasonic surgical handpiece to result in improved control responsiveness during aspiration. The system comprises a console including a vacuum pump. The system includes a cassette comprising a joint that divides a vacuum path into at least two flow paths. A first joint port couples to a first flow path. A second flow path is coupled to a second joint port, a third flow path is coupled to a third joint port, and a fourth flow path is coupled to a port on a surgical waste receiver. A first sensor senses pressure in the fourth flow path and provides a waste receiver pressure signal. A second sensor senses pressure in the third flow path and provides a tip pressure signal. The controller controls a position of a first vent valve and a second vent valve based on the waste receiver pressure signal and the tip pressure signal, respectively.