How to prototype analog audio processing?
A simulation will not tell you anything about the subtleties of what a circuit sounds like, so you should plan to breadboard your ideas with real components. Breadboard sockets are particularly useful at audio frequencies, since you're not dealing with RF or high impedances.

However, as Neil_UK says, simulation can tell you whether an idea is feasible at all, or help you debug a circuit that isn't behaving as expected.