Vehicle engine sound enhancement

A system comprising:

• circuitry for providing a fundamental frequency corresponding to the RPM of an engine of a vehicle;
• circuitry for determining a plurality of harmonics of the fundamental frequency;
• circuitry for determining a target shape of the plurality of harmonics, the target shape comprising, for each of the harmonics of the plurality of the harmonics, a gain value as a function of the RPM of the engine;
• circuitry for determining an accelerator pedal position (APP) based gain comprising a gain value as a function of an accelerator pedal position;
• circuitry for determining a speed based gain comprising a gain value as a function of a difference between a set maximum speed of the vehicle and a measured vehicle speed of the vehicle;
• and
• circuitry for combining the plurality of harmonics, the target shape of the plurality of harmonics, the engine harmonic enhancement gain, and the engine harmonic enhancement modification gain to produce a set of harmonic enhancement signals.

A method comprising:

• providing a fundamental frequency corresponding to the RPM of an engine of a vehicle;
• determining a plurality of harmonics of the fundamental frequency;
• determining a target shape of the plurality of harmonics, the target shape comprising, for each of the harmonics of the plurality of the harmonics, a gain value as a function of the RPM of the engine;
• determining a speed based gain comprising a gain value as a function of a difference between a set maximum speed of the vehicle and a measured vehicle speed of the vehicle;
• determining an engine harmonic enhancement (EHE) gain comprising a gain value as a function of an accelerator pedal position and the speed based gain;
• combining the plurality of harmonics, the target shape of the plurality of harmonics, and the EHE gain to produce a set of engine harmonic enhancement signals.