[sdiy] Odd? filter topology question

[Grant Richter]

It is a version of the Electronotes 4 pole 24 dB/oct filter. This is the
same as the Moog ladder filter, but with less distortion. It was also used
in the Star Synare, with darlingtons for buffers instead of FETs.

> From: Duane R Balvage <dbalvage at ptdcs2.ra.intel.com>
> Organization: Intel
> Date: Thu, 04 Apr 2002 09:59:45 -0800
> To: Synth-DIY <synth-diy at dropmix.xs4all.nl>
> Subject: [sdiy] Odd? filter topology question
> 
> Hello all -
> 
> I am ressurecting from the dead, one Octave Cat synth (rev 1), and I had a
> question
> about the filter topology...
> 
> It appears to be a 4 pole filter composed of 4 CA 3080s (can type(!) ) 4 metal
> foil
> caps, and
> Fet buffers between each stage.
> 
> Is this some sort of 4-pole state-variable? Or am I missing something?
> 
> -Duane
> -- 
> 
> 
> 
> "The IQ and the life expectancy of the average American recently
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> -George Carlin 
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