Time is the first dimension of hearing.
It is always present either explicitly or implicitly in any representation of sound including those assumed to exist in the auditory system . Pressure is also a dimension of the sound wave but representations always require a measure of level, or magnitude, and perhaps for this reason, magnitude is not normally referred to as a dimension of a representation. As sound approaches the ear canal, it interacts with the head and the concha with the result that the version of the sound at the eardrum is different in the two ears. The interaural timing and intensity differences are used by the auditory system to determine the location of the source relative to the head. The sound is, then, concentrated by the eardrum and middle ear bones.