The principle you mentioned was more common with TOS (organ type) polysynths or enseble keyboards in the 70s, such as the Polymoog or Korg PE Series. later, in the 80s, there were only few designs with shared filter, such as the Korg Mono/Poly. Korg did this design on the 800 mainly for cutting costs. The DW series do have the same VCF chip (NJM2069) but one for each oscillator. Interesting to see the reduction of components. Polysix does use 2 mask programmed MCS48 MCUs while Poly 800 uses one of these MCUs with external ROM.
--- In korgpolyex@yahoogroups.com, Paul Cunningham <paul@...> wrote:
>
> the main difference with the Poly-800 series as opposed to other polysynths of the era is that all eight oscillators are first routed through their own amplifier, and then through a ∗shared∗ 4-pole filter. this makes it a unique instrument to play harmonically -- something between a polysynth and a monosynth. all of the other synths you mentioned use the more traditional polysynth architecture which provides each voice it's own filter and amplifier, with the filter before the amplifier. -pc
>
>
> On Feb 14, 2011, at 3:44 PM, k9k9dog wrote:
>
> > wondering what a block diagram of this synth
> > would look like. as in, a kind of signal flow
> > diagram or something like that.
> >
> > just wondering about theoretical possibilities
> > (and impossibilities) for future ideas;
> > for instance, taking separate harmonics and
> > rerouting them, ringmod options, stuff like that?
> >
> > i'd like to know more about what's going on inside,
> > how it compares,say, to juno's jp's and jx's. some
> > kind of assessment/description of the osc+filter etc.
> > circuitry.
> >
> >
>