Adaptive equalization compensation for earbuds

A processor of an earphone, the processor configured to perform adaptive equalization operations comprising operations to:

• determine a transfer function of a signal path from a speaker of an earphone to an error microphone of the earphone;
• adjust the transfer function based on a relationship between a first acoustic pressure at the error microphone and a second acoustic pressure at an eardrum of a wearer of the earphone;
• and
• apply the adaptive equalization operations to drive the speaker, by compensating a frequency response of the error microphone based on the adjusted transfer function to match a frequency response at the eardrum for frequencies below a threshold frequency.

An earphone comprising:

• a speaker configured to transmit a signal;
• an error microphone configured to capture the signal transmitted by the speaker as a first acoustic pressure;
• a processor;
• and
• a memory coupled to the processor to store instructions, which when executed by the processor, cause the processor to perform adaptive equalization operations comprising:
• determine a transfer function of a signal path from the speaker to the error microphone;
• adjust the transfer function based on a relationship between the first acoustic pressure at the error microphone and a second acoustic pressure at an eardrum of a wearer of the earphone;
• and
• apply the adaptive equalization operations to drive the speaker by compensating a frequency response of the error microphone based on the adjusted transfer function to match a frequency response at the eardrum for frequencies below a threshold frequency.