A vehicle sound synthesis system is provided with a loudspeaker and a controller. The loudspeaker projects sound indicative of synthesized engine noise (SEN) within a cabin of a vehicle in response to receiving a SEN signal. The controller is programmed to generate the SEN signal; and receive a first input indicative of an engine start command. The controller is further programmed to, modulate a characteristic of the SEN signal to align with a corresponding engine operating characteristic during starting conditions in response to the engine start command; and provide an adjusted SEN signal including the modulated characteristic to the loudspeaker.