Certain embodiments provide an acoustic wave touch bar system and method of use. Certain embodiments include a bar having two portions of reduced cross-section forming an acoustic cavity in the portion of the bar between the reduced cross-sections. The system includes an acoustic wave transducer positioned on the acoustic wave cavity, wherein the transducer generates an acoustic standing wave that is substantially trapped in the acoustic cavity. The system also includes a circuit coupled to the transducer and responsive to a change in an output of the transducer to detect a touch on a touch surface of the bar. The circuit may be a programmable and/or adaptive circuit, for example. The circuit may detect a change in an exponentially decaying response of the transducer indicating that the touch surface of the bar has been touched.