Re: [LAD] Paul's Extreme Sound Stretch

On Sep 30, 2010, at 11:16 PM, fons@email-addr-hidden wrote:

> On Thu, Sep 30, 2010 at 09:23:08PM +0200, Robin Gareus wrote:
>
>> Back when I was introduced to FT in some Physics lecture I was happy
>> that I was able to use it and completely forgot to check the history :)
>> Probably related to why I favored experimental Physics over Theory.
>
> If you're still living in Paris, make sure to visit the 'Musée des
> Arts et Métiers' one day. Quite a nice place for vintage experimental
> physics. It's also the place where the final mad scene of Umberto Eco's
> novel "Foucault's Pendulum" is situated. The pendulum itself used to be
> there, but it's now at the Panthéon.
>

I know the latter of course, but I've not yet been to the Musee des Arts et Metiers.
Thanks for the hint, I'll definitely schedule a visit.

There's so many hidden treasures here in plain sight one hardly knows where to start.

>>> And I guess this is where the windowing comes in. Calculate the spectrum
>>> of small pieces instead.
>>>
>> correct.
>>
>> Furthermore there are different kind of windows (here a window refers to
>> a block of audio-samples) and windows can overlap. That's where it gets
>> complicated.
>
> Even windows won't save you from apparent madness. Imagine a signal
> consisting of all zero samples, except one every second which has
> value 1. Such a signal contains all frequencies that are a multiple
> of 1 Hz, up to half the sample frequency. Those frequencies are present
> all the time. Now take a window of say half a second. If it includes a
> pulse you get more or less the same spectrum again. If it doesn't, you
> get nothing... even if the frequencies should be there :-)
>

to come back to the beginning: that's why paulstretch does allow to specify the window size.

Cheers!
robin

> Ciao,
>
> --
> FA
>
> There are three of them, and Alleline.
>

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Received on Fri Oct 1 04:15:03 2010