[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

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



On Tue, 25 Feb 2003 03:47:43 +1100, Matt Flax <flatmax@IEEE.ORG> worte:
>On Sat, Feb 22, 2003 at 04:31:10PM +0800, Chen-gia TSAI wrote:
>> This success of autocorrelation in modeling pitch extraction is, at
>> least for me, very impressive. I also noticed that the autocorrelation
>> function has been used to analyze musical timbres in
>...SNIP...
>Autocorrelation dates back to an article by Licklider (1951 in
>Experientia). The concept that autocorrelation correctly models the
>complex neural processing which is anatomically present in the inner ear
>is a big question mark in my opinion. The beginning of my views can be
>found here (this is only a place model- a temporal model is in the pipe
>line): http://mffmpitch.sourceforge.net/

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.

Jim Beauchamp
University of Illinois at Urbana-Champaign
j-beauch@uiuc.edu