When devices such as telephone handsets, headsets, headphones, hearing aids and hearing protectors are electro-acoustically tested, mannequins known as Head and Torso Simulators (HATS) are used to replicate the upper part of the human body. They allow researchers to simulate Head Related Transfer Function, which is the process by which sounds are changed by the time they reach the human eardrum. The mannequins' calibrated pinna (outer ear) simulators have traditionally been represented through a series of two-dimensional cross-sectional profiles – this is the industry standard for pinnas on HATS. Now, as part of a revision of that standard, the Acoustics Team from the UK’s National Physical Laboratory (NPL) have created a three-dimensional pinna that overcomes the limitations of the 2D variety.
Read the full article: Setting a new standard for 3D model ears