Here's a sound demo of the mod that we've been discussing. It's a very basic demo, but you'll definitely get the idea of how defeating/removing this VCF really opens up the sound...
https://soundcloud.com/synthhacker/korg-polysix-sound-of-removingPretty dramaitc, eh? I call this one "The Snappy Mod". And, because it can be done non-destructively, I highly recommend it!
A full post with schematics, pics, and graphs will come later.
Enjoy!
Chip