Journal of the Acoustical Society of America
The impedance of the middle-ear air space was measured on three human cadaver ears with complete mastoid air-cell systems. Below 500 Hz, the impedance is approximately compliance-like, and at higher frequencies (500-6000 Hz) the impedance magnitude has several (five to nine) extrema. Mechanisms for these extrema are identified and described through circuit models of the middle-ear air space. The measurements demonstrate that the middle-ear air space impedance can affect the middle-ear impedance at the tympanic membrane by as much as 10 dB at frequencies greater than 1000 Hz. Thus, variations in the middle-ear air space impedance that result from variations in anatomy of the middle-ear air space can contribute to inter-ear variations in both impedance measurements and otoacoustic emissions, when measured at the tympanic membrane.
© 2005 Acoustical Society of America.
Stepp, Cara E. and Voss, Susan E., "Acoustics of the Human Middle-Ear Air Space" (2005). Engineering: Faculty Publications, Smith College, Northampton, MA.