Head-related transfer functions encode how the head and pinna shape spatial hearing

Evidence

HRTFs or HRIRs are measured in free-field conditions with the sound source (a loudspeaker) placed in desired positions, for example, 2 metres from a subject at each azimuth and elevation angle of interest (Møller, 1992). An anechoic room can be used for the measurement, but the reflections from walls can also be eliminated by windowing the response to before the arrival of the first reflection. Small microphones are used to capture the response close to the entrance or inside the ear canal. In the former case, the ear canal is typically blocked by the microphone set-up, as illustrated in Figure 12.4a, or it can be kept open. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1410 (#expands, via linked claim)

Categorization

• XREF: connects to: The pinna’s folded shape encodes sound direction as spectral echoes; HRTFs encode direction through head, ear, and torso shape filtering; Adults relearn spatial localization within six weeks of altered pinnae (+13 more)

Related

• HRTFs encode direction through head, ear, and torso shape filtering (similarity 0.92)
• Large diverse datasets of human HRTF and ear geometry are now being collected (similarity 0.92)
• Head-related transfer functions encode all body-induced spectral and temporal sound changes (similarity 0.92)
• Head-related transfer functions are measured with in-ear microphones in anechoic chambers (similarity 0.91)
• Head and pinna scattering imprint direction-dependent spectral notches onto the ear signal. (similarity 0.87)
• HRTF definition normalizes ear responses by the head’s absence (similarity 0.86)
• Binaural microphones capture exact tympanum signals but depend on one’s own head shape (similarity 0.86)
• Head movement and pinna shape resolve cone-of-confusion ambiguities (similarity 0.85)
• Head-related transfer functions spatially pan monaural sources by modeling each ear’s directional filter response (similarity 0.85)
• Elevation localization relies on pinnae spectral cues encoded as HRTFs (similarity 0.85)
• Pinna, head, and torso shapes encode spatial direction into ear-canal sounds (similarity 0.84)
• The pinna’s folded shape encodes sound direction as spectral echoes (similarity 0.84)
• Each person’s directional hearing is calibrated to their own ear shape (similarity 0.84)
• Individual pinnae shapes make spatial hearing uniquely personal and learned (similarity 0.83)
• Each person’s unique ear shape requires individualized acoustic rendering for 3-D audio (similarity 0.83)

Broader Connections

• Head-related transfer functions are measured with in-ear microphones in anechoic chambers #expands (0.85) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1410
• Binaural microphones capture exact tympanum signals but depend on one’s own head shape #expands (0.80)
• Head separation between ears produces arrival-time and intensity cues for direction #expands (0.78)
• Outer and middle ear transfer function determines loudness across frequency. #complicates (0.72)