Re: Time and space (Alain de Cheveigne )

Subject: Re: Time and space
From:    Alain de Cheveigne  <alain(at)LINGUIST.JUSSIEU.FR>
Date:    Tue, 10 Jun 1997 08:40:33 +0200

On Mon, 9 Jun 1997 15:00:33 +0100 Niel Todd wrote:
>"The next phenomenon we consider is that of virtual pitch
>shift. Virtual pitch shift is described as the shift in
>perceived pitch of a complex in which all the partials have
>been shifted by a constant amount, so that they are no longer
>harmonic. In the literature there are generally two distinct
>accounts of pitch shift (Hartmann and Doty, 1996).
...
>It is known that there are some small
>discrepancies between current timing models and experimental
>data. e.g. the slope of the pitch shift in the case of Meddis
>and Hewitt (1991) and the predicted mistuning of the
>fundamental in the case of Hartmann and Doty (1996). It may be
>that the hybrid model proposed here may account for these small
>discrepancies of the timing models, but this requires testing."

The phenomenon reported by Hartmann and Doty (JASA, 1996) had nothing
to do with a virtual pitch shift.  Hartmann and and Doty studied the
shift of the pitch of individual _partials_ (including the fundamental)
within the context of a harmonic complex.  Subjects systematically
overestimated the mistuning of the partial.  They were not asked
anything about the low pitch (virtual pitch) of the complex.

Look at
        Moore, B. C. J., Peters, R. W., and Glasberg, B. R. (1985).
        "Thresholds for the detection of inharmonicity in complex
        tones,"  J. Acoust. Soc. Am. 77, 1861-1867.
and
        Darwin, C. J., Ciocca, V., and Sandell, G. J. (1994).
        "Effects of frequency and amplitude modulation on the pitch of
        a complex tone with a mistuned harmonic,"  J. Acoust. Soc. Am.
        95, 2631-2636.
for experiments that explored the effect of similar mistunings on the low
pitch of the complex.

Alain