One embodiment provides a device comprising a speaker driver including a diaphragm. The device further comprises a controller configured to receive a source signal for reproduction via the speaker driver, determine an estimated displacement of the diaphragm resulting from the reproduction of the source signal, and generate a control voltage based on the estimated displacement and threshold information relating to safe displacement of the diaphragm. An actual displacement of the diaphragm during the reproduction of the source signal is controlled based on the control voltage.