Middle ear acts as a band-pass filter attenuating 6 dB per octave

Evidence

The transfer functions of the external and middle ear must be emulated with appropriate filters before processing the signal with a filter bank model. Various approaches can be exploited for this purpose depending on the requirements of the application. The best accuracy in emulating the external ear is achieved using measured HRTFs of an individual subject or of a dummy head. Typically, the middle ear transfer function is considered a band-pass filter with, say, a 6-dB/octave decreasing frequency response at frequencies below 800 Hz as well as above 1.5 kHz, as shown in Figure 7.5. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1608