On Tue, May 26, 2015 at 11:56:39PM -0700,
ultragalore@... [korgpolyex] wrote:
> Hi All,
>
>
> I have a hard time finding the modification for routing an external audio signal through the 2069 filter. Somewhere on the internet someone proposed to switch the noise signal but that does not sound very logical to me. I thought to just add a signal to pins 20/21 which are the normal 'signal in' pins.
>
>
> I am a bit worried about 'breaking' the 2069 though, also heard they're pretty delicate...
>
>
> Does anyone have the good solution for this?
Build an external filter :-)
By the time you've mucked about with this, you could have built something like the Yusynth Steiner Synthacon clone, which is four transistors, ten diodes and a bunch of passives. Oh, and Yves Usson used it in his design for the Arturia Minibrute!
Now, I wonder if you could replace the 2069 with such a beast. Or even add eight and have a properly polyphonic synth - with suitable software mods.
--
Gordonjcp MM0YEQ