I have always wondered about the difference, if any, the values of resistors would have on the design of an op amp circuit. What I mean is, let's say that you were to design an op amp circuit for a gain of approximately ten times. You could use a 10k resistor as the input resistor to the op amp and a 100k resistor as its feedback resistor. Is there an impedance difference, noise difference or any other difference if you were to use, for example, a 100k ohm input resistor and a 1 meg resistor as the feedback resistor? Thanks.