The role of the pinna in human localization.

The pinna, or ex ternal ear, has been shown experim entally to perform an acoustical tran sfo r­ m ation essential to localization in hum an hearing. The m athem atical form of th e tran sfo rm a­ tion is given, the inverse to the transform ation is shown to exist, and a theory of localization constructed from the evidence. The theory is extended to reverberation and o ther facets of hum an hearing. The basic theorem applied to the study is 6 in order to know, th e inverse to the transform ation of perception m ust be construc ted ’.