DMQ QSV Series sound velocity or nodularity gauges are cost effective instruments that can be used to determine material types based on their sound velocity and in the foundry industry the QSV is used to determine cast iron types based on the sound velocity of the actual casts. In all cases sound velocity measurements are obtained by first measuring the thickness of the test piece that can be entered into the QSV manually or automatically with the use a digital caliper interface available in our QSV DLC models.