[PD] curve fitting help?

[Martin Peach]

Maybe start with your x values somewhere negative, since exp(0) = 1. In
your graph it looks like around 0.6 would be 0, so subtract 0.6 from x,
looks like maybe 1000*exp(x-0.6).

Martin

On Wed, Oct 22, 2014 at 2:03 PM, Dan Wilcox <danomatika at gmail.com> wrote:

> Howdy all,
>
> I’m *almost* done with my rjlib compatible s_minimoog abstraction for the
> rc-patches, but I need help finding the right curve for the ADSR controls.
> I used block diagrams and the Minimoog Service Manual to build the dsp
> chain. What I have now can give a *reasonably* accurate rendition of
> Minimoog patches from sheets found online (ELP Aquatarkus, for instance).
> What I did notice in comparing it to the Arturia Mini V AudioUnit minimoog
> simulation, is that the knob curves for frequency are different form what
> I’ve been able to do, so some patches aren’t quite *right* yet.
>
> Basically, I’ve tried a number of different exponential and power curves
> but can’t get one that has the long, low slope on the low end. All of my
> curves rise too quickly. In any case, this is a curve fitting problem and
> this is the data I’m working with. The mapping I want is 0 - 1 to 20 0
> 20kHz. And no, I don’t to just stick a log hsl in there :D
>
> Any help would be appreciated so I can get this out there and start using
> it!
>
> pos freq
> 0.000 0
> 0.125 83
> 0.250 362
> 0.375 456
> 0.500 768
> 0.625 1750
> 0.750 6300
> 0.875 12750
> 1.000 25000
>
>
>
>
> --------
> Dan Wilcox
> @danomatika
> danomatika.com
> robotcowboy.com
>
>
>
>
>
>
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