RE: Tuning Digest 1412 - Integer ratio harmonics/Additive analysis

The reference given by Patrick Ozzard-Low on Frequency ratios of spectral
components of musical sounds is of interest to me and I plan to copy the
article and read it at first opportunity (next trip to UC San Diego library).
It has been over five years since I did intensive work improving a frequency
tracking / additive analysis computer program system which I'd received from
the Univ. of Illinois' CERL Music Lab.
I used an autocorrelation technique to track frequency, using trial window
sizes for paired "windows" of duration one estimated period of the fundamental
- e.g. 2.27 milliseconds for a pitched sound of fundamental frequency 440 Hz.
Then, using a frequency vs. time basis line, I would use a Fourier analysis
algorithm to track partial amplitude and phase, window by window, over the
course of the sound. I added empirically calibrated error correction
modifications to the basic program and tested these using artificially
constructed "sounds" having time varying amplitudes coupled with time varying
frequencies.
I do not recall specific numbers (these are "buried" in my not very well
organized logs and notes), but I believe that in cases of "well behaved"
sounds - normal pitched singing, instrument notes at moderate volume, etc. the
method faithfully yielded, for a partial, the number of cycles it went through
over a sound's course (from under a second to several seconds for most sounds
I analyzed) accurate to .01 of a cycle. Thus I believe the method would, for
example, give AVERAGE frequency results for, say, the second partial of a 440
Hz fundamental analyzed over one second to an accuracy of about one part in
88,000.
If the results of my work would be of significant value to a researcher or
researchers in the field, I would like to make my programs &c. available to
them. Some work would be needed to make my software "user-friendly", although
someone with a technical background (C programming, basic scientific
mathematics) might be able to make use of it quickly.
I'm currently working on another research project (preparing listener
intonation response - e.g. preference, descriptive observations of contrasts,
etc. - tests to be given in late June/early July for research purposes to high
school/junior high school summer music campers - I'm doing another post
regarding this). This limits the amount of time which I can presently give to
dealing with the additive analysis material, but if there is a serious need it
might meet I certainly would like to make it available to meet that need.

Dave Hill

>Wandering tonics are another typical example used against JI renditions
>of many common-practice pieces.

I'm always prompt to point out that I personally wandering tonics to be
more of an intriguing musical effect than a liability, so I guess I may as
well point it out this time too.

Oh, I suppose I just did, eh?