The auditory system acts as a band-pass filter at each signal frequency.

Evidence

The action of the basilar membrane can be thought of as being equivalent to a large number of overlapping band-pass filters, or a “bank” of band-pass filters, each responding to a particular band of frequencies (see Chapter 1). Based on the idealized filter response curve shape in Figure 2.10(a), an illustration of the nature of this bank of filters is given in Figure 2.10(b). Each filter has an asymmetric shape to its response, with a steeper roll-off on the high-frequency side than on the lowfrequency side; the bandwidth of a particular filter is given by the critical bandwidth (see Figure 2.8) for any particular center frequency. It is not possible to be particularly exact with regard to the extent to which the filters overlap. A common practical compromise, for example, in studio third octave graphic equalizer filter banks, is to overlap adjacent filters at the −3 dB points on their response curves. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 595 (#expands, via linked claim)

Categorization

• XREF: connects to: Filter banks split broadband signals into sub-bands much like cochlear hearing does — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 396; The envelope of each auditory filter output is processed by a modulation filterbank; A threshold-spike autocorrelation model transforms auditory filter output into a periodic spiketrain. (+6 more)

Broader Connections

• Each basilar membrane location acts as a bandpass filter tuned to a center frequency #expands (0.95) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 595