Preformed Perfecty except the "Can you hear it" part. the only thing I can say without exposure is "Make it louder" or "Shake it harder" if you know what I mean
I would say the same as Perfelti, make more of a point of hearing the coin in the can.
Another thing, show that the coin wont fit through the top of the can before cutting it. Adds so much more to the effect, although I personally like to give the can still containing the coin to the spectator.