This Recommendation specifies the electroacousticai characteristics of Head and Torso Simulators (HATS) to be used for telephonometric measurements. Both the sound generation and sound pick-up characteristics of these devices are specified.
ITU-T P.58-1996 history
1996ITU-T P.58-1996 Head and Torso Simulator for Telephonometry - Series P: Telephone Transmission Quality; Objective Measuring Apparatus Study Group 12