The Quad VCA is made with a homemade double side pcb without metalized holes ( soldering both sides ... ). Op-amps for CV controls are TL074/84. Op-amps on the "audio" path should be good quality ones , unlike what i did here :the prototype is fitted with LM358 on pictures... .Something like OP275 , NE5532, OPA2604 will be good for this module ..
pcb with soldered components received,
2x SSM2164 - v2164 replacement each 4,80€
lm358 or OP275
frontpanel can be ordered on Schaeffer (ca.60€)
quadvca.pdf -> Schematic
quadvca_bom.txt -> BOM
quad_vca_1.fpd -> FPE file