AM8069

Aura Filter & VCA

This module uses the NJM2069 chip to provide a Low Pass voltage controlled filter and a VCA in one module. This replicates the filter used in the Korg DW and DSS synths and samplers in the 1980's. This is a 2 or 4 pole OTA filter design that Korg first used in the DW6000 in 1985.

This is a warm sounding filter with smooth frequency control and a resonance that gradually increases up to full self oscillation, a sound very reminiscent of the mid 1980's. The difference between 2 and 4-pole modes is not dramatic, with the 2-pole mode providing a more gradual cutoff slope and silky sound.

This module is an accurate reproduction of the Korg low pass voltage controlled filter, using the original NJM2069 OTA chip in the filter core. The design has been updated to use modern components and to interface to Euro Rack signal and CV levels. it delivers a very warm and smooth sound.

There are front panel controls for adjusting the Cutoff Frequency and Resonance as well as the level of 2x control voltages, the VCA level and 2x audio signal inputs. Resonance is smooth and controllable to self-oscillation.

There are six 3.5mm jack sockets on the right of the front panel;

2x Audio Signal Inputs (10V peak to peak)
2x Control Voltages for the VCF (0V to +5V)
1x Control Voltages for the VCA (0V to +5V)
Audio Signal Output

The slope of the filter can be switched between 2 and 4 poles using a small red push button, and a red LED with lens shows the filter slope selected.

https://www.amsynthstore.co.uk/AM8069_VCF__VCA/p1461448_16788165.aspx