[sdiy] Nonlinearities in IR3109 filters

[Aaron Lanterman]

On Wed, 2 Aug 2006, Magnus Danielson wrote:

> So, I have never viewed OTAs but rather the filter topology as being 
> what requires more or less control of the feedback. In the EMS 
> VCS-3/Synthi-A there is no real limitation, rather you vary the amount 
> of overdrive and you do hear the shift in character as you turn it 
> deeper into the self-oscillation range of the resonance knob. The point

Interesting point about the synthi. With its diode-ladder structure, the 
poles and the way they migrate work differently than they do in a 
transistor-ladder or OTA-series (where the stages are buffered). So I'd 
expect it to have different resonance characteristics. Somewhere in my 
notes from last Fall I have worked out where the poles go.

- Aaron