Wiardgroup

> Thank you all very much for the response! Especially Doc,still i'm 
> wondering one thing: both modules use analog and digital noise, why 
> is that? What is the difference? And why both use these different 
> noise sources for different applications?
> 

Because analog and digital noise generators sound different. Analog noise is "hiss" and has a 
gaussian level distribution. Digital noise can sound like "hiss" under some circumstances, but 
can be changed a lot, it has a uniform level distribution.

Here is a chart from Federal Scientific, which shows statistical properties of waveforms 
including analog and digital noise:

http://www.musicsynthesizer.com/Circuitry/probability.htm

The Noise Ring outptus waveforms 6 and two different versions of 10. The "Change" control 
essentially controls auto-correlation.