Discrete Core Ladder VCF

The ACL Discrete Core Ladder VCF is a classic transistor ladder filter with a fully discrete, low-noise, low-distortion audio path. Its four stages each have a buffered output, usable separately and at once.

Key features

• 6, 12, 18 and 24 dB/octave outputs, each stage 90° out of phase with the previous one, so mixing them, some inverted, gives other slopes and filter types
• BOOST restores the low frequencies a ladder loses as the resonance rises
• Self-oscillates down to below 1 Hz
• The Q LIN switch keeps the resonance independent of the cutoff or lets it fall with it
• Three mixed audio inputs, 1V/OCT and two attenuated CV inputs for the cutoff, and a CV input for the resonance
• Temperature-stabilised cutoff