“Oberheim Xpander” Voltage Controlled Filter (multi mode)
The A-106.6 is a multimode filter that is based on the filter circuit of the Oberheim Xpander/Matrix 12. The module features 15 different filter types with 8 filters available simultaneously. A toggle switch is used to switch between 2 filter groups.
These filter types are available: 1L (6 dB low pass), 2L (12 dB low pass), 3L (18 dB low pass) 4L (24 dB low pass), 1H (6 dB high pass), 2H (12 dB high pass) 3H (18 dB high pass), 2B (6 dB band pass), 4B (12 dB bandpass) 2N (notch), 3A (allpass), 2H1L (band pass , 12 dB high pass / 6 dB low pass) 3H1L (band pass, 18 dB high pass / 6 dB low pass) 2N1L (notch/6 dB low pass), 3A1L (allpass and 6 dB low pass)
There is voltage controlled resonanceand for filter group 2 (2L, 4L, 2B ...) self oscillation is possible. All standard VCF controls are available: manual filter frequency control Frq, one control voltage input with attenuator (FCV2) and one without attenuator (FCV1, ~ 1 V/octave). Voltage controlled resonance with manual control (Q) and a CV input with attenuator (QCV).