Wind-machine

[harrybissell at prodigy.net]

OH no no no...
You DO NOT want a low pass filter for the "wind"
you want a band pass filter !!!

The old PAiA 2720 had a bandpass filter based on a twin-tee design (transistor only) that would work fine.
It's tuned by diode inpedance, but for slow moving envelopes the control feedthrough will be nil.

Check out their old "surf synthesizer" design (I could scan in if you want...) They use several transistor "flip-flops" to generate a pseudo-random wave... and this generates the surf...

Make the LPF a BPS and It would BE a wind generator!
(It has VCA and LP-VCF already, just switch to bandpass and play with the values)

A Triangle gen won't give a very convincing wind sound...

Try using multiple band-pass filters all modulated separatly and it will be even better.

The higher the Q of the filters... the worse the windstorm...

H^)


 ---- On Feb  7 Niklas =?iso-8859-1?Q?R=F6nnberg?= <nikro at itn.liu.se> wrote: 
> Hello!
> I would like to build a little and simple wind-machine. Yes, I know that
> I could do that with almost any synth, but I want a stand-alone
> wind-machine. 
> Ok, I need one noise-generator, one LFO, one VCF, and a VCA. But I have
> one more wish; I just want to use transistors! 
> The LFO should do tri, and why not sinus. The VCF should be a Low Pass
> filter. Both the VCF and the VCA can be controlled by the LFO, but the
> VCA should have a pot where I can control the initial level.
> Any comments? Any ideas?
> Regards
> /Niklas
> ______________________________________________
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