Not surprising it's a lot cheaper. Triggering the notes is pretty simple. About half the Kenton kit is processing poly-aftertouch and integrating that into the CS80. And, again, that's just for MIDI in, not out.
Mark looks like he does some interesting work but his website doesn't have anything on it yet.
--- In yamahacs80@yahoogroups.com, Rainer Keizer <rainer.keizer@...> wrote:
>
> There's a guy in the Netherlands called Mark Cox who makes a MIDI kit for
> the CS 60, I don't know if he also made something for the CS 80. His
> website - only useful for contact info - is: ∗cox∗-∗electronics∗.com . The
> CS 60 kit is quite a bit cheaper than the Kenton kit at about EUR 400
> ∗including∗ fitting it, instead of the EUR 755 for the Kenton kit including
> fitting!