来到耳廓与外耳道的某些频率的声压,通过外耳集音作用,使其增幅后再到达鼓膜,这种机能就叫外耳的音响机能。通常认为,外耳的音响机能在2500—4000频率间可使其声压增幅达24—38.65分贝。耳廓连同外耳道具有类似圓锥形喇叭的集音作用,外耳的圆锥形喇叭其内角为25°, The sound pressure of some frequencies coming to the pinna and external auditory canal, through the effect of the sound collection of the external ear, increases its amplitude and then reaches the tympanic membrane. This function is called the acoustic function of the external ear. It is generally believed that the acoustic performance of the outer ear increases its sound pressure by 24-38.65 dB over the 2500-4000 frequency range. Auricle with external auditory canal has a similar cone-shaped speaker sound collection role, the conical horn of the outer ear of its internal angle of 25 °,