Apple Inc.
Self-Equalizing Loudspeaker System

Abstract:

An impulse response is computed between i) an audio signal that is being output as sound by a loudspeaker that is integrated in a loudspeaker enclosure, and ii) a microphone signal from a microphone that is recording the output by the loudspeaker and that is also integrated in the loudspeaker enclosure. A reverberation spectrum is extracted from the impulse response. Sound power spectrum at the listening distance is computed, based on the reverberation spectrum, and an equalization filter is determined based on i) the estimated sound power spectrum and ii) a desired frequency response at the listening distance. Other aspects are also described and claimed.