A loudspeaker system includes a driver in an enclosure that provides a back volume which is sealed with respect to acoustic pressure waves produced by a driver diaphragm. An external microphone is located outside the back volume. An internal microphone located inside the back volume. A computational unit is coupled to the external microphone and the internal microphone and configured to determine a transfer function for an equalization filter. The transfer function determination is responsive to the external microphone and the internal microphone. A digital signal processor is coupled to a signal source, the driver, and the computational unit. The digital signal processor is configured to implement the equalization filter as determined by the computational unit, create a filtered audio signal from the signal source, and provide the filtered audio signal to the driver.