Systems and methods for generating natural directional pinna cues for virtual sound source synthesis

A sound device comprising:

• at least four physical sound sources, wherein, when the sound device is used by a user, two of the physical sound sources of the at least four physical sound sources are positioned closer to a first ear of the user than to a second ear, and two of the physical sound sources of the at least four physical sound sources are positioned closer to the second ear than to the first ear, and wherein, for each ear of the user, at least two physical sound sources of the at least four physical sound sources are configured to induce natural directional pinna cues associated with different directions of sound arrival at the ear of the user;
• a processor;
• and
• memory storing instructions executable by the processor to:
• receive and process at least one audio input signal and distribute at least one processed version of the audio input signal at least between 4 kHz and 12 kHz over at least two of the physical sound sources of the at least four physical sound sources for each ear,
• wherein the processing of at least one audio input signal comprises applying at least one filter to the audio input signal;
• and
• the at least one filter comprises a transfer function;
• wherein the transfer function of the at least one filter approximates at least one aspect of at least one measured or simulated head related transfer function (HRTF) of at least one human or dummy head or a numerical head model;
• wherein the transfer function of the at least one filter approximates aspects of at least one of interaural level differences and interaural time differences of at least one HRTF of at least one human or dummy head or numerical head model;
• and
• wherein either no resonance and cancellation effects of pinnae are involved in generation of the at least one HRTF, or resonance and cancellation effects of pinnae involved in the generation of the at least one HRTF are at least partly excluded from the approximation.

A sound system comprising:

• at least four physical sound sources each configured to emit sound from respective directions, the at least four physical sound sources including a first group of at least two physical sound sources of the at least four physical sound sources and a second group of at least two physical sound sources of the at least four physical sound sources, the first group configured to induce natural directional pinna cues associated with different directions of sound arrival at a first selected position, and the second group configured to induce natural directional pinna cues associated with different directions of sound arrival at a second selected position;
• a processor;
• and
• memory storing instructions executable by the processor to:
• receive and process at least one audio input signal by applying a filter to the audio input signal, the filter having a transfer function approximating at least one aspect of at least one measured or simulated head related transfer function (HRTF) of at least one human or dummy head or a numerical head model, and
• distribute at least one processed version of the audio input signal at least between 4 kHz and 12 kHz over each of the first group and the second group of physical sound sources by scaling the at least one processed audio input signal with an individual panning factor for each of the physical sound sources of the first group and the second group,
• wherein the processing of at least one audio input signal comprises applying at least one filter to the audio input signal;
• and
• the at least one filter comprises a transfer function;
• wherein the transfer function of the at least one filter approximates at least one aspect of at least one measured or simulated HRTF of at least one human or dummy head or the numerical head model;
• wherein the transfer function of the at least one filter approximates aspects of at least one of interaural level differences and interaural time differences of at least one HRTF of at least one human or dummy head or numerical head model;
• and
• wherein either no resonance and cancellation effects of pinnae are involved in generation of the at least one HRTF, or resonance and cancellation effects of pinnae involved in the generation of the at least one HRTF are at least partly excluded from the approximation.