With the Phoenix system, you just get one of thier boards (2K2 or P5) and then customize it fit you locomotive. You down load a sound file and load it into the board. Then you can tinker with it all you want. One by the way, you must have their computer interface to do this or you tell the dealer you are getting the board from which sounds you want loaded before he sends it to you. It is not like a Sierra system where you buy the board already setup with a preprogrammed chip for your engine.