Korg MS20 filters

[Martin Czech]

Yesterday I also wanted to have a closer look to the Korg MS20 filters
(hyperreal). Oh dear, Korg-35 "modules" instead of a plain schematic.
The really important parts of the filter are missing.
Some special Korg IC? 
Now I looked into the archive, later models used LM13700,
no sound change was observed, and could find this version:

http://www.mindspring.com/~vco/maxx2/page_015.html

Could some guru please confirm, that this (nice) cicuit is equal to the
newer MS20 models?

J.H. ?

If not, where can I obtain an original drawing other than
the hyperreal ?

m.c.