retrolefty:
fungus:
You could try putting bigger resistors in there, eg. in the megaohm range. The Arduino ADC input has 100 megaohm resistance so there's still some margin to work with.Yes, but the analogRead() function works best and is recommended being driven by a voltage source of 10K ohms or less
That would suggest there's some capacitance in the input stage of the chip. If that's the case then a small resistor could be needed for sampling (eg.) a 10kHz signal. For a low frequency signal though, it would make no difference.
I'd say "try it and see" before adding opamps (or whatever). There's nothing to lose except two resistors.