Acoustic immitance is used to verify the functionality of the middle ear by measurements with the 226 Hz tympanogram, which in normal cases generates a type A graph; however more detailed information about the functionality of middle ear using higher frequency is necessary in order to enable more specific diagnostics. This research characterized the results using tympanometries 678 Hz, 800 Hz and 1000 Hz, using impedanciometer AT235H, in adults with normal hearing, without any hearing impairments and with type A tympanogram to 226Hz. The study was done with 150 samples, and it shows additional information about the physiology of the middle ear using higher frequencies, in terms of ear canal volume, admittance and pressure, showing a tendency towards higher values when the applied frequencies are increased.