Boomstar Modular 8106 Filter
Designer Tim Caswell: "The 8106 is a 6db/oct hi-pass filter followed by a recreation of the Roland® IR3109 module, which is a 4 pole, 24 db/oct voltage controlled lowpass filter with voltage controlled resonance. Three dual OTAs with similar topology to the BA662 used in the Jupiter 8 (and the IR3109 module) were employed, one amp for the hi-pass filter, four (with added buffers) for the low-pass, and one for the resonance. This filter takes a wide range of input signals, and tracks control voltage extremely well. Tap points are available for 6db, 12db, and 18db/oct. Although the topology is similar to the 4075, the tonality, especially when overdriven, is distinct..."