Doepfer

For what it's worth, the Analogue Solutions sy02 is an ms-20 filter 
clone. The filters are in series (just as the korg's are). input>HP>LP>
VCA. It sounds really close to my ms-20, but has the advantages of 1, 
being completely modular and 2, being gear I don't mind taking out of 
my studio. Although, I usually just take the micro-modular out (more 
portable and less fragile).

-andrew