Anything you can do to lower the pressure will make it quieter. But to do that you'll need a regulator you can adjust pretty easily. You'll need a spring kit too, lighter valve spring means less force is required to open the valve means less noise. Higher flow valve would require less pressure as well.
Don't be expecting to get your spyder as quiet as a cocker or shocker. A spyder is a spyder is a spyder. It can only be upgraded so much.
-Micah