one/F noise source ckt?

Kirke Sonnichsen kirke at lmi.net
Thu Aug 3 15:54:37 CEST 2000


Didn't Bob Moog have some clever way of making a -3dB filter
for the pink noise source in the MiniMoog?

I seem to remeber reading something about that but, it was
such a long time ago...

- Kirke
(stochastically speaking)


>
>The above article is correct in that the 1/f curve is the power distribution
>and NOT the amplitude distribution. The diffrence is highly important since it
>gives -3 dB/oct instead of -6 dB/oct. Now, a normal RC filter is -6 dB/oct, so
>it will not be enougth.
>
>Doing a true -3 dB/oct filter REALLY IS as hard as fetching half an electron!!!
>
>One method to approximate a -3 dB/oct filter which is available for DSPs is to
>create a -3 dB/oct frequency distribution and then use the inverse Fourier
>transform in order to generate the impulse responce that could be used in a
>FIR filter. There are naturally limits with using this method, but it can be
>used. Hmm... I wonder how the coefs will look!!!
>
>Cheers,
>Magnus





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