SynthEdit does not perform low-level electronic circuit simulation or modeling.
We don’t model that much detail (resistor and capacitors). We do however model 1-pole filters (which are a combined resistor and capacitor). You can use a level-adjust to reduce/increase voltage, somewhat like a resistor. SE does not in general model individual components, think more like a Moog with “modules” of pre-built functions.
More information: http://en.wikipedia.org/wiki/Electronic_circuit_simulation