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Re: Traveling waves or resonance?



Still facing ingratitude from Christian who won his quarrel on autocorrelation
together with Peter, I do not expect much consent with Martin if I take up
Dick's mention of critical bandwidth coinciding with width of Tianying Ren's
traveling wave. The reason for me to do so is my curiosity how many
such local traveling waves might exist at a time.

Inspired from recorded AN patterns, I tend to imagine up to 15 TWs forming a
fairly coarse but frequency-analog bar code. Spectrograms can show too many
lines. Spectral resolution is limited.

Does it really make sense to defend the old models of just one hydromechanical
long traveling wave transmitting energy from base to apex? All of the presumably
up to 15 local cochlear amplifiers are electrically powered.

I tried to interpret the phenomenon of travel inside a standing envelope of less
than 1 mm width like an advantage because it provides bandwidth for subsequent
cepstral analysis after downsampling. Given, there is not much evidence for the
waves suggested by Andrew, and Martin's idea of resonant hair cells is also not
yet the whole story, then Andrew and Martin nonetheless deserve high
appreciation for pointing at some weakness of the traditional models. What about
the discrepancy between a wide frequency range of hearing and less varying
stiffness and width of BM, David Mountain did perhaps not yet distinguish
between the range of hearing (down to about 20 Hz) and the range of CF (down to
about 100 Hz).

While I suggest to finally abandon all long-wave and transmission-line models, my
favorite for the traveling wave within a narrow standing envelope is based
on what I read from Ren, Russell, Mountain, Dallos, and many others.

Eckard