User headphones are calibrated in real time to improve the reproduction accuracy of recorded audio content. Microphones of a type used to record the audio content (including their orientation and recording characteristics) are characterized to indicate a first audio coloration. Audio playback devices of a type used to process the audio content are characterized to indicate a second audio coloration. Headphones of a type corresponding to the user headphones are characterized to indicate a third audio coloration. An equalization signal is computed based on the audio colorations, and is applied to calibrate the user headphones during playback of the audio content. A database of the characterizations is maintained so that calibration of different models of headphones using different playback devices can be accomplished for audio content recorded using different models of microphones.