Re: Fast Fourier Filtering of an Instrument's Harmonics

On Sep 4, 8:25 am, "Salviati" <eckard.blumsch...@xxxxxxxx> wrote:
"BigBlueOx" <eclectic.sou...@xxxxxxxxx> schrieb im Newsbeitragnews:46913818-2c5f-4f7e-bfae-81e48d4cd24a@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
...

So now lies my
problem once again of having too many harmonics resonating to pick out
the right tone from a spectrum.
...
My main question is still, what is the most
efficent way of filtering out a fundament frequency of an instrument
when there are so many harmonics coming from that instrument? Is the
FFT the wrong approach?

Maybe, our auditory system performs something like an autocorrelation. At
least I found out that while my vovel 'a' is composed of many spectral
components with no clearly dominating size, the belonging autocorrelation
clearly shows a distinct common fundamental period.

BTW, while FFT might be extraordinarily efficient and easily available,
cochlea cannot perform complex calculus and the hair cells could not rectify
magnitude.
Accordingly, cosine transform is more natural. If you are interested you
might look athttp://home.arcor.de/eckard.blumschein.de/M283.htmland
around.

Regards,
Salviati
http://



One thing I did notice about my small tuner is that it does not tell
you what register of the note you are playing only that you are
playing that certain note.  Is this the trick?  I suppose I could use
the lowest octave I can think of and then see what note frequency all
the dominating harmonics are evenly divisible by... But this seems
like cheating.

Thanks for any help!

BTW anyone interested can get my tuner here:

http://www.silencetostatic.com/software/guitartuner1.0.zip

I am thinking the same thing that the ears pick out the sounds they
like and leave the rest behind. I spent so long incorporating the FFT
into my program I would like to use it, if I can't get that one to
work I will try the cosine.

THanks!
.

Relevant Pages

  • Re: Best way to measure precise harmonics?
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  • Re: Fast Fourier Filtering of an Instruments Harmonics
    ... problem once again of having too many harmonics resonating to pick out ... the right tone from a spectrum. ... efficent way of filtering out a fundament frequency of an instrument ... playing that certain note. ...
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  • Re: Best way to measure precise harmonics?
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