Phase shifts between the ears can substitute for onset time delays in detecting sounds.

Evidence

Assuming that the phase shift of the tone presented to one ear is produced by adding a tone of the same frequency, but out-of-phase by 105°, the phase shift of the sum of the two tones is changed in relation to the situation without the additional tone. If this complex is presented to one ear and a pure tone without an additional tone is presented to the other ear, it is possible to present two sounds to the ears that differ little in amplitude but differ in phase. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 1625

Categorization

• QUESTION: Why exactly 105° out-of-phase addition — is that a sign convention or chosen for some threshold property?