Diffuse‐field sound pressure transformation to a manikin's ear, head surface, and torso surface Free

The transformation of a diffuse sound pressure field to a manikin's ear, head surface, and torso surface was measured in a 425 m³ reverberation chamber between 0.2 and 10.0 kHz using 1/3‐octave bandwidth random white noise. The maximum gain in sound pressure level at the microphone in an earlike coupler relative to the diffuse‐field pressure was measured to be 15 dB at 2.7 kHz. Further measurements show that the pressure level buildup at the manikin's head surface and torso surface. when bare (acoustically hard), ranges from ∼0 dB at low frequencies to ∼+4 dB at high frequencies. Absorptive clothing reduces the pressure level buildup on the torso, where body‐worn hearing aids or dosimeters may be located, to values ranging between −1/2 dB to +1 dB for frequencies ⩾1.6 kHz. Theoretical predictions of the diffuse field gain at the “eardrum” and head surface compare well with the experimental data.