Arcenson 904A VC LFP (PCB)
new from arcenson in quebec city, canada
904a vc low pass filter pcb
from arcenson:
"The 904A Low Pass Filter attenuates frequencies above the fixed control voltage cutoff point at a rate of 24dB per octave. The cutoff point {cutoff frequency} is voltage controlled through the control input jacks. The sum of the applied control voltages doubles the frequency of the cutoff point for each one volt increase {volt per octave standardization at input named 1V/oct}. For compatibility reasons the 2 other control inputs have a gain raised to accommodate 0-5v control as opposed to Moog’s 0-6volts levels. The regenaration potentiometer varies the amount of internal feedback, creating a resonant peak at the cutoff frequency. This resonant peak will break into oscillation at clockwise settings of the regeneration pot, creating a voltage controlled sine wave generator. The fixed control voltage pot covers a 12 volts {octave} range. The overall range of the FCV pot is determined by the Frequency Range switch which moves the frequency cutoff range in two-octave steps. The basic cutoff frequency of the lowpass Filter is determined by the combination of Fixed Control Voltage and Frequency range in addition to the control input signals. An increase in regeneration narrows and increases the strength of the cutoff frequency peak, while decreasing the amplitude of the lower frequencies."
more information including spec, BOM etc here: http://www.arcenson.com/projects/Modular/M104A_Lowpass_Filter_Moog_904A_clone/