AW: [sdiy] Build a Lorenz Attractor

[harrybissell]

Howdy all...

I just did a spice simulation of the Lorenz circuit, and (surprisingly) it works
as
advertized.  You need to make the circuit "imperfect" for it to start... I
introduced
2mV of opamp offset into the center (y) opamp.

(I also found that Chua's oscillator will simulate as well. Now if I could only
build a good
noise source in spice - that would run at 'real time' speeds I mean)

Also... there is a freeware program called "Fractint"  (rev20 iirc) that has the
Lorenz
attractor as a fractal type. You might experiment with that to quickly find
other
weights for the variables that hold promise.

H^) harry



Nils Pipenbrinck wrote:

> Mike wrote:
> > Ian - thanks for pointing that out - interesting circuit! Wonder how it
> > would sound if  used in place of the usual 3-phase modulation generator
> > in a triple-delay string ensemble chorus. Perhaps un-random enough to be
> > useful.
>
> That's a great idea.. I have a 6 stage analog phaser that I control from a
> three phase sin lfo (two stages per phase). Sounds pretty good, but it has
> still a very predictable filtersweep. This lorenz attractor circuit might be
> worth trying out.
>
> To bad I don't have any analog multiplier chip at home. The circuit would be
> easy enough to breadboard this evening. But I'll try it out in digital this
> weekend. If anyone is interested in samples let me know..
>
>   Nils