Hi Ingo
Thanks for this info
I have heard the term "sallen & key" before, but I have no idea about
it's specific meaning. I also heard that the MS20 filter is also
a "sallen & key", but this problably has transistors instead of
diodes

With all the current excitement (also shared by by myself) about the
most recent cadidate modules (MS50 filt + complex VCO), I suppose
that a new filter module for a rather obsure module such as a
700/770/800dv, is presently not very relevant. Maybe some day ....

just listen at the 800dv mp3's at www.amazona.de for the
typical "old" Korg sound for your enjoyment ..

kind regards
Joost

--- In Doepfer_a100@yahoogroups.com , "selfoscillate"
<synaptic_music@y...> wrote:

>
> hello,
>
> i found some info on the internet regarding old korg filters,
> but i don't know if the information is correct.
>
> the korg 700/700s/800dv have sallen&key type 2-pole filters
> with diodes. the circuitry is described as hybrid( ).
>
> the korg 770 filters are also sallen&key 2-pole with diodes,
> but the circuitry is discrete.
>
> finally the ms50 is sallen&key 2-pole with a diode array.
>
> as i said, i don't know if this is true or false information,
> i just found it on a japanese homepage.
>
> best wishes
>
> ingo
>
>
>
>
> --- In Doepfer_a100@yahoogroups.com , Florian Anwander
> <Florian.Anwander@c...> wrote:
> > Hi Ingo
> >
> > > maybe we can come close enough to the sound of the old
> > > korgs with the planned ms20 modules. also we have to make
> > > sure that we don't get a filter overkill. together with the
> > > ms20 filters we have more than 20 filter in the doepfer range.
> > The 800DV synth sounds very nice. I think it is based on two 12dB
> > OTA-based Filters. Those 12 dB filters sound definitely different
> from
> > the A121 though they use basically the same circuit principles.

It

> could
> > be worth as an replacement of the A121.
> >
> > Florian