Method, apparatus and article of manufacture for monitoring and characterizing the operation of a transducer (i.e., motor or pump) downhole. In particular, transducer RPMs are determined by analysis of acoustic information. An acoustical source (signal generator) located on a downhole tool (e.g., a drill string) creates acoustic energy which is received and processed by a receiving unit, which may be located at the surface of a wellbore. The acoustical source is operably connected to the transducer, so that the frequency of the signal produced by the acoustical source corresponds to the speed of the transducer. The acoustic signal of the acoustical source may then be isolated from other acoustical energy produce by downhole equipment, such as a drill bit. Having determined transducer speed by isolation of the acoustic signal, other operating parameters may be determined. Illustrative operating parameters include torque, flow, pressure, horsepower, and weight-on-bit.