On Wed, 13 Oct 2004 17:01:59 -0700, Bob Cain
wrote:



Ryan wrote:

Terms? As in how many instruments I want to end up with? Or by what
specs I will measure the orignal soundfile? If the later, do you mean
something like bitrate, samplerate, something else? Why would the
number of terms be greater than the samplerate? Is matlab an audio
tool. Probably just a math program right? So I would enter in pcm
info and run the calculations and then use the output to create a pcm
file? Sorry so many questions.

Ryan, most of what you are asking about is well beyond the
state of the art, the art being DSP.

I'm trying to follow the thoughts... it appears what he wants is a
computer program that does with an orchestra what one does with a
synthesizer to imitate the sound of a musical instrument ("imitative
synthesis"). I suppose nowadays you could write a program that scans a
digitized audio recording and makes a patch (or orchestral score) that
somewhat crudely approximates the sound, but it could surely be
tweaked by hand/ear to make it better, or perhaps a synthesist (person
making a synth patch) would just start over and make something that
sounds better/closer. I doubt that having it do a mathematical
operation such as a fit a least-squares match of the FFT would make it
anywhere near the "original sound" as would a person experienced in
doing these things.
But to make "arbitrary sounds" with orchestral instruments ... the
only thing I've heard that's anything like this is on Peter Shickele's
"Upper West Side" where he says something about hearing Vivaldi one
more time. The strings play throught the melody once, then they play
the beat of the melody with hip-hop record-scratching sounds. It was
hard to believe my ears. Is there a video? I'd like to SEE these
string players reproducing this speed-up-and-slow-down
record-scratching sound.


I would suggest that
you go to comp.dsp and set forth what it is you want to get
more specific feedback about it.

Like MIDI output of polyphonic audio input, this technology is not
quite (actually nowhere near) ready for prime time.



Bob

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