Piezoelectric electronic audible alarms work by converting the user input voltage to an appropriate oscillating signal that is applied to a sounder element that is mounted in a housing. This piezoelectric sounder element consists of a metal disc that has a special ceramic material bonded to it that physically bends when voltage is applied to it.

Direct drive transducer devices do not have any included DC circuitry, so the user must apply a sine or square wave with the appropriate rated frequency. A square wave will typically result in more sound level than a sine wave. The higher the peak-to-peak voltage applied (up to the maximum rated voltage), the higher the resulting sound level.