Re: Do you recognize this sound?


Don Pearce wrote:
> On 5 May 2005 01:35:27 -0700, "Herbert Blenner" <a1eah71@xxxxxxx>
> wrote:
>
>
> >
> >If your sonar is an accurate representation of the 900 Hz component
> >then I would appreciate further details on how you extracted it from
> >the other signals.
> >
> >Herbert
> >
>
> If you want to extract the signal yourself using your FFT, then it is
> quite simple. Run the FFT. Set all the values up to the 800Hz point
to
> zero. Do the same for points from 1kHz upwards. Now run the IFFT and
> you have a filtered version of the original, with just the 900Hz
> signal and a bit of noise - similar to what I posted, but without the
> extra joke effects.
>
> d
> Pearce Consulting
> http://www.pearce.uk.com

Thanks for the advice, Don.

I have tried the technique and found that transient response of the
filter to the rapid shifts of the signal dominate the output.

Herbert

.

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