Non-invasive ultrasound measurements are not currently widely used, due to limitations in high temperature transducer technology and signal processing. These have been addressed in the ultrasound program in our laboratory, where high frequency sampling using our own high temperature probes is now available. The need for high frequency sampling of the ultrasound signal to resolve measurements of transit time (and amplitude) to the required accuracy requires handling of large amounts of data, and in the case of actual polymer processing such as extrusion, data processing needs to be real time. A computer controlled system for the acquisition of such data is described here, with examples of the sensitivity of the measurements to a range of polymer melt process variables, including polymer composition and fillers, for extrusion and injection moulding processing.