Black Dual VCF

Two identical multimode VCFs on Erica's AS3320 chip, with simultaneous HP, BP and LP outputs, linked controls for stereo, series or parallel routing to a summing output and a 16 band spectrum analyser, in 18 HP from Erica Synths' Black Series, retired.

Key features

• CUTOFF and RESONANCE for each filter; LINK sets both filters from CUTOFF1 and RESONANCE1 (CUTOFF2 and RESONANCE2 disabled)
• IN LVL, RESO CV and C-OFF CV (attenuverters) for each, with IN, R CV and C CV
• HP, BP and LP outputs for each, all at once; the HP / BP / LP switch picks what goes to SUM OUT
• The routing switch chains the two filters to SUM OUT in series or in parallel
• 16 lamps, a spectrum analyser of the summing output, 1 kHz to 16 kHz
• +40 mA, -36 mA, 35 mm deep