Impedance matching is a transfer of the incoming vibration from the tympanic membrane to the oval window of the middle ear. Middle ear is an efficient impedance transformer. Three features of the middle ear minimize energy loss amplifying the pressure transferred from the tympanic membrane to the oval window. They include:
- areal ratio ( the area of the oval window is smaller the tympanic membrane);
- level ratio (the length of the malleus is longer than the incus;
- buckling action (the pressure is transmitted from the centre of the tympanic membrane).