Earcanal Pressure Generated by a Free Sound Field

Abstract

Pressure levels generated at the entrance to the earcanal by progressive waves from a point source at a distance of 1 m were measured for a group of 10 subjects. Individual curves are presented at six azimuthal angles of incidence. Measurements at 0[degree], 45[degree], 90[degree], and 180[degree]cover the frequency range 02-14 kcps. Measurements at 270[degree] and 315[degree] entend to 9 kcps. Certain features (maxima at 2. 4 and 13 kcps, minima at 4 and 10 kcps) appear to be relatively independent of angle of incidence. Others (peak at 7 kcps) have strong azimuthal dependence. Normal modes of the concha may have an important role in the 6- to 10-kcps region.