[sdiy] 2164 Korgasmatron VCF

[David G. Dixon]

In simulation, if I feed the input into both the HP and LP destinations on a
single filter, I do indeed get a kind of gentle notch.  The minimum
amplitude at the cutoff frequency (with zero resonance) is 6db (i.e., 50% of
the input amplitude).  It's not a sharp notch like one would expect from a
proper notch filter, but more of a smooth dip in (log) amplitude at the
cutoff frequency.  Is that going to sound like much?

Is this what the "notch" setting on the other clones achieves as well?  I
can't see any other way to hook the thing up, so I'm presuming so, but I'd
love to know for sure before I commit to it on the PCB.


> Now that I've got it all laid out in the original topology (fixed HP and
> LP
> stages), I think I'll redo the whole thing and put in switches to allow
> each
> section to be HP, LP or N (a shameless copy of the MOTM 420).  I'm
> presuming
> that N is obtained simply by feeding the input to both the HP and LP
> destinations (?).  I'll find out soon enough in simulation, but it makes
> sense.