Re: FFT - Spectrum Analyzer

[Francesco Potortì]

>> > Why would one perform a Fourier-based analysis on something so clearly 
>> > non-stationary as music? I think wavelets are the tool of choice.

To know what are the spectral components in different moments.

>> There is short time FFT. FFT with buffer 0.1 second buffer length is
>> often quite usable and still has 10Hz frequency resolution (more or less).
>
>...but Fourier is predicated on the whole signal having the
>characteristics of the observed portion. One can perform short duration
>transforms, I agree - but this is typically done for ensemble averaging
>purposes, such as Welch's method. 

Only if yu are interested in the characteristics of the whole signal.
Not if you are interested in seeing as those vary with time.

>Let me ask it another way: what question is answered by performing any
>kind of Fourier analysis on music? 

The same that you answer by looking at a real-time spectrogram such as
found on mixers, for example.  Or any spectrum analyser.

>Or perhaps yet another way: Could you compare Shakespeare and Proust
>using Fourier-based methods on the spoken word?

Maybe.  We'd need a computational linguist to answer this.

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