Phase-based localization sensing has a hard frequency ceiling near 1.6 kHz

Evidence

For low-frequency signals up to about 1.5 kHz, the auditory system is sensitive to the phase difference between the narrowband signals in each auditory band. Note that the cue is still often called the ITD, although in some cases the slightly more precise term interaural phase difference (IPD) is used. For frequencies higher than about 800 Hz, the size of the head is comparable to or larger than half the wavelength of the sound, making phase differences ambiguous. Nevertheless, humans are sensitive to the IPD at frequencies up to about 1.6 kHz (Blauert, 1996). ITD cues are still extracted at higher frequencies by the auditory system from the delays between temporal envelopes of the signals. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1430

Categorization

• XREF: The head-size-to-wavelength ambiguity threshold (~800 Hz where half-wavelength meets head diameter) echoes other engineering tradeoffs where a physical dimension and signal wavelength interact — connects to wave mechanics, antenna theory, and any physical sensing designs that must stay below a resolution cutoff. — connects to: Phase-based localization tops out at 743 Hz at 90 degrees — David Howard, Jamie Angus, coustics and Psychoacoustics, 719; Phase-based sound localization becomes ambiguous beyond 180 degrees phase shift; High-frequency tones produce ambiguous azimuthal localization due to phase wrapping. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 1467 (+4 more)

Broader Connections

• Phase-based localization tops out at 743 Hz at 90 degrees #corroborates (0.95) — David Howard, Jamie Angus, coustics and Psychoacoustics, 719
• Phase-based sound localization becomes ambiguous beyond 180 degrees phase shift #qualifies (0.85)
• High-frequency tones produce ambiguous azimuthal localization due to phase wrapping. #corroborates (0.85) — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 1467
• Pure-tone localization errors spike specifically around 2000 to 4000 Hz #contradicts (0.75)
• Sound localization is best for frontal sounds and at low and high frequencies #complicates (0.75)
• Front and back sound localization requires other mechanisms than ITD #expands (0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 717
• Phase-change detection yields a critical bandwidth of 150 Hz at 1 kHz #expands (0.70) — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 901