Sound reaching the far ear must travel around the head
Evidence
Unfortunately, this equation is wrong. It underestimates the delay between the ears because it ignores the fact that the sound must travel around the head in order to get to them. This adds an additional delay to the sound, as shown in Figure 2.25. This additional delay can be calculated, provided one assumes that the head is spherical, by recognizing that the distance traveled around the head for a given angle of incidence is given by: — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 710
Categorization
Category: Causal Relationships
- XREF: Connects to the interaural time difference concept used in binaural recording and HRTF-based spatial audio discussed elsewhere in the book.
Related
- Interaural time delay calculations must account for sound traveling around the head (similarity 0.90)
- Ear offset from the head’s center makes arrival time shift with source azimuth (similarity 0.89)
- Head size alone predicts interaural time differences well across azimuth angles (similarity 0.88)
- Head separation between ears produces arrival-time and intensity cues for direction (similarity 0.86)
- Head shadow attenuates sound arriving at the far ear unless the source is centered (similarity 0.86)
- Head shading creates interaural level differences used for sound localization (similarity 0.86)
- Head shadowing gives roughly 6 dB interaural amplitude difference near 1.85 kHz (similarity 0.86)
- Head intensity-shading fails below the frequency where head size reaches one-third wavelength (similarity 0.85)
- Interaural time delays alone cannot fully determine sound source direction (similarity 0.84)
- Directional hearing rests on interaural time and intensity differences. (similarity 0.84)
- The ear sits 8 cm off-center, so source-ear distance changes with azimuth (similarity 0.84)
- The ear resolves low-frequency direction by measuring phase shift (similarity 0.83)
- The ear is far less sensitive to phase than to amplitude of frequency components (similarity 0.83)
- Phase delays beyond 180 degrees make direction judgments ambiguous (similarity 0.83)
- Head orientation is necessary because interaural level differences plateau off-midline (similarity 0.83)
Broader Connections
- Head separation between ears produces arrival-time and intensity cues for direction
#expands(0.85) — David Howard, Jamie Angus, coustics and Psychoacoustics, 696 - Ear offset from the head’s center makes arrival time shift with source azimuth
#corroborates(0.80) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1416 - Head shadowing gives roughly 6 dB interaural amplitude difference near 1.85 kHz
#expands(0.75) — Toole, Floyd E, Sound reproduction- the acoustics and…, 418