Shoulder reflections imprint identifiable arcs on measured head-related impulse responses.

Evidence

Perhaps the most interesting details in the figure are the faint arcs or half-arcs which coincide at 0.5 ms with source directions −45◦and 225◦. The arcs or half-arcs seem to have their apexes at temporal positions of about 1.5 ms, 2.5 ms, and 3.5 ms. The first arc, with apex at 1.5 ms, is caused by the reflection from the shoulders. When the source is above the subject, the sound reaching the shoulders is reflected back to the ears, and thus it travels a distance about 30 cm longer than the direct sound, which causes the 1-ms delay seen in the figure. When the source is lower in the median plane, the extra travel time is shorter, and the shoulder contribution arrives earlier. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1421

Categorization

• DEFINE: Explains how to read HRIR arc structure as causal traces of shoulder reflections.
• QUESTION: Why must the source rotate with ear canal at center for the direct-path peak to remain at fixed latency?
• XREF: connects to: Shoulder reflections create a distinguishable 1-ms delay in head-related impulse responses — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1421; Head, torso, and shoulder acoustics shape the localization cues reaching each ear. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1404; Head-related transfer functions encode all body-induced spectral and temporal sound changes — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 1534

Broader Connections

• Shoulder reflections create a distinguishable 1-ms delay in head-related impulse responses #exemplifies (0.85) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1421
• Head, torso, and shoulder acoustics shape the localization cues reaching each ear. #expands (0.78) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1404
• Head-related transfer functions encode all body-induced spectral and temporal sound changes #expands (0.75) — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 1534