System and method for compensating memoryless non-linear distortion of an audio transducer

A system for compensating digital audio samples d(n) of a digital audio signal for an audio transducer, comprising:

• memory for storing a lookup table (LUT) for the audio transducer, said LUT including scale factors of the transducer's memoryless nonlinear distortion over the phase plane indexed by sample amplitude, velocity pairs;
• and
• a processor that measures an amplitude a(n) of the digital audio signal each digital audio sample d(n), estimates a velocity v(n) of the digital signal for each digital audio sample d(n), extracts a scale factor from the LUT using the measured a(n), v(n) pair, and scales the amplitude a(n) of the digital audio sample d(n) by the scale factor.

A system for compensating digital audio samples d(n) of a digital audio signal for an audio transducer, comprising:

• memory for storing a phase plane representation of the audio transducer, said phase plane representation embodying scale factors of the transducer's memoryless nonlinear distortion over the phase plane as a function of amplitude and velocity, wherein the phase plane representation is a polynomial equation whose only independent variables are the measured signal amplitude and signal velocity;
• and
• a processor that measures an amplitude a(n) of the digital audio signal for each digital audio sample d(n), estimates a velocity v(n) of the digital audio signal for each digital audio sample d(n), extracts a scale factor from the phase plane representation using the measured a(n), v(n) pair, and scales the amplitude a(n) of the digital audio signal by the scale factor.

A method of determining a phase plane representation of scale factors for compensating memoryless nonlinear distortion of an audio transducer, comprising:

• synchronized playback and recording of a test signal through the audio transducer;
• and
• storing a ratio of the test signal amplitude s(n) to the recorded signal amplitude r(n) as a scale factor in a lookup table (LUT) indexed by a signal amplitude, signal velocity pair.