[sdiy] Random Voltage Generator & ADV/Cookbook

[John Greczula]

Magnus Danielson wrote:
> 
> From: Scott Gravenhorst <music.maker at gte.net>
> Subject: Re: [sdiy] Random Voltage Generator & ADV/Cookbook
> Date: Sun, 11 Nov 2001 13:27:01
> 
> > A ranodom voltage *is* noise.
> 
> I think he wants slow changes. There is basically two types, just slow
> variations, or random steps.

Yes! Slow changes/variations are what I'm after, not sample and hold.

 > The slow variation version is just a lowpassfiltered noise source, if
> you vary the lowpass filters frequency, you have more or less of the
> quicker movements.

So by running a 'regular' white or pink noise source through and LPF and use
that to modulate a filter, I'll get the same result?
 
> The random step version is a noise source with a sample-and-hold
> circuit controled by an LFO. As you vary the frequency of the LFO, you
> vary the length of each step.

Yep, I understand the S&H via LFO (an SH-101 was my first synth) but I'm 
looking for smooooooth changes. :0)
 
> Both these can use a common noise source, the after-processing is
> simple to duplicate.

So in a circuit where you can vary the speed of the random voltage,
what is happening? Are you simple changing the cutoff frequency of a LPF filter
the noise is going through?
 
> You DO get noise outputs as a side-effect.
> 
> Cheers,
> Magnus - contributing to the noise - that must make me a noise generator...

:0))

Thanks Magnus!
-- 
John Greczula
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