Expander Module for Doepfer A-127
Not for sale, but easy to build.
Switchable filters + Audio Multiple for each circuit,
The bottom switch can put the module in a mode so that both levels of the filter and the original can be controlled with attenuator 1 ( audio level in )
Find the modification info at http://patchpierre.blogspot.nl/2010/12/modifications-ii-127-triple-resonance.html
http://patchpierre.blogspot.nl/2010/12/modifications-iii-127-triple-resonance.html