A broadband ultrasonic transducer device (UTD) is disclosed that utilizes a plurality of narrow-band piezo electric elements grouped into single-frequency sub-arrays to provide a relatively simple, highly-reliable deterrent unit (DU) capable of emitting ultrasonic energy over a wide coverage area and at a sound pressure level that meets or exceeds other DU approaches. In an embodiment, the broadband UTD includes a housing portion configured to couple to a plurality of piezo sub-array plates. Each piezo sub-array plate includes a plurality of pockets or cavities to receive respective narrow-band (e.g., 1-3 kHz) piezo electro transducer elements with characteristics, e.g., geometries and material composition, that cause each to emit ultrasonic energy at a particular resonant frequency. A controller of the UTD implements a control scheme to emit ultrasonic energy in a plurality of output modes including a white noise node and a single-frequency mode for deterrence applications.