Another filter based on the LM13700 chip. A lot of filters use this chip and have similair designs. I have to double check the schematics on the skullandcircuits.com but this could be based on the MS 20 design by Korg (didn’t check yet when posting this). It has it’s own sound that’s one reason to put this in your rack. It has lox pass, band pass and high pass outputs that enable mixing them together with a mixer.
https://www.skullandcircuits.com/vcf-3/
Difficulty to build: Easy.
Not that many parts and well spaced.