The Tympanic Membrane
The tympanic membrane or "eardrum" receives vibrations traveling up the auditory canal and transfers them through the tiny ossicles to the oval window, the port into the inner ear.
The eardrum is some fifteen times larger than the oval window of the inner ear, giving an amplification of about fifteen compared to a case where the sound pressure interacted with the oval window alone.
The tympanic membrane is very thin, about 0.1 mm, but it is resilient and strong.(Zemlin)
Active graphic
You may reach information about the nearby structures of the ear by clicking on the item of interest on the illustration.
Frequencies for maximum sensitivity of human hearing
The hearing curves show a significant dip in the range 2000-5000 Hz with a peak sensitivity around 3500 -4000 Hz. This is associated with the resonance of the auditory canal. There is another enhanced sensitivity region at about 13,500 Hz which may be associated with the third harmonic resonance of the auditory canal. The high sensitivity region at 2-5kHz is very important for the understanding of speech.
Ossicle Vibration
The vibration of the eardrum is transmitted to the oval window of the inner ear by means of the ossicles, which achieve an amplification by lever action. The lever is adjustable under muscle action and may actually attenuate loud sounds for protection of the ear.
