Tiptop Z2040 4-Pole VCF - Manual (Page 9)

VC-FM / VC-FM IN
The VC-FM knob attenuates the VC-FM IN
Input impedance: 22K Ohm
Input Range: +/-2.5V*
Gain / VC-Gain
Gain knob sets the input gain to the filter regardless
of the VCA position.
Input impedance: 30K Ohm
Input Range: +5V*
* Input range is not limited and can exceed these
values
Impedance:
Audio In: 35K typical, 10K at maximum gain
Audio out: 220 Ohm
Power :
+/-12V +/-15V *
* Powering the Z2040 from +/-15V is supported, some
slight variation in control range may occur.