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Re: Can a timbre affected by a shifted virtual pitch evoked by double-spaced harmonics?



Just to understand the nomenclature here, by "autocorrelation" do we
mean autocorrelation of the pressure signal waveform? There are two types
that are used for pitch detection that I know of, multiplicative and
subtractive. Here is a nice review of these types:

Alain de Cheveigne, "YIN, a fundamental frequency estimator for speech
and music", JASA 111(4), 1917-1930 (April 2002).

de Cheveigne developed a refinement of the subtractive method which seems
to be very accuracte for speech and solo music. However, I don't think
it has been tested on inharmonic signals, like the ones Chen-Gia gives.
I should warn that that paper describes an F0 estimation _method_
rather than a pitch perception _model_.Ţ An earlier paper (JASA 103,
1261-1271) deals with pitch and is probably easier to read.

Method and model have been tested on inharmonic signals.Ţ They behave
as expected from the quasi-periodic nature of the signals.Ţ The
various pitch shifts observed experimentally are well accounted for,
as Meddis and Hewitt (1991) or Cariani and Delgutte (1996) have shown.

As de Boer pointed out in his thesis (1956) and in a famous chapter
(1976), autocorrelation and variants on one hand, and pattern
matching (e.g. Terhard and others) on the other make essentially
equivalent predictions.Ţ

The "first effect" results because the models follow the pseudoperiod
(or pseudofundamental) of the stimulus.Ţ The "second effect" results
from (a) greater emphasis on components within a "dominant region" of
the spectrum, and (b) combination tones.

de Boer's (1976) chapter is hard to find but well worth searching for.

Alain

---
de Boer, E. (1956). On the "residue" in hearing. unpublished doctoral
thesis, University of Amsterdam.
de Boer, E. (1976). On the "residue" and auditory pitch perception.
Handbook of sensory physiology. W. D. Keidel and W. D. Neff. Berlin,
Springer-Verlag: 479-583.
Cariani, P. A. and B. Delgutte (1996). ┼gNeural correlates of the
pitch of complex tones. I. Pitch and pitch salience.┼h J.
Neurophysiol. 76: 1698-1716.
Cariani, P. A. and B. Delgutte (1996). ┼gNeural correlates of the
pitch of complex tones. II. Pitch shift, pitch ambiguity,
phase-invariance, pitch circularity, rate-pitch and the dominance
region for pitch.┼h J. Neurophysiol. 76: 1717-1734.
Meddis, R. and M. J. Hewitt (1991). ┼gVirtual pitch and phase
sensitivity of a computer model of the auditory periphery. I: Pitch
identification.┼h J. Acoust. Soc. Am. 89: 2866-2882.
Meddis, R. and M. J. Hewitt (1991). ┼gVirtual pitch and phase
sensitivity of a computer model of the auditory periphery. II: phase
sensitivity.┼h J. Acoust. Soc. Am. 89: 2883-2894.
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--
Alain de Cheveigne'
Ircam - CNRS,
1 place Igor Stravinsky, 75004, Paris, FRANCE.
email: Alain.de.Cheveigne@ircam.fr, phone: +33 1 44 78 48 46