Available as an assembled Module and as a DIY project.
No info about availability.
Filter
https://www.modulargrid.net/e/random-source-variable-q-vcf
The Serge Extended Variable Resonance filter (VCFQ) is probably the most famous filter of the Serge system and one of the essential Serge modules. It is an excellent, extremely versatile general-purpose VCF that provides simultaneous low-pass, high-pass, band-pass and notch (band-reject) outputs combined with unique flexibility. Its trigger in, LOW mode and self osciallation allow a variety of uses from Oscillator to VC processing.
These merchants probably sell this module. Huh?
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