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Re: Is there considerable phase locking up to 6 kHz?
Dear Christian, Dick, Roy, and others,
listening to Cheng-Gia's sound file for his example, I also hear that
something "goes up". It sounds like a mixture of pitch and timbre change,
where neither can be heard clearly.
I would suggest, however, that we do not any longer call a timbre change a
chance of "place pitch".
There is no physiology of a "place pitch", and this concept should be given
up. All physiological evidence describes a mechanism of pitch extraction by
periodicity detection in the auditory midbrain. There is a physiology of a
"place timbre" however.
We see two main pathways on which period information can reach the period
detectors in the midbrain:
a) the proper pitch pathway, which delivers period coding, by phase locking,
of resolved harmonics, and
b) a secondary pathway, which delivers temporal delay signals that were
originally encoded for the purpose of sound localization.
Pathway (b) can be activated by many delay signals, such as envelop
repetitions or noise repetitions.
In Cheng-Gia's example both pitch pathways and the "place timbre" pathway
are activated. What the brain does with this muddle depends on its memory
and its "good will".
Neuroscience of Music
S-671 95 Klässbol
web site: http://w1.570.telia.com/~u57011259/index.htm