Electronic Impressionist Mimics Car Engine Sounds

I'm not sure whether or not I believe this thing, but apparently you hook it up to your rev counter and vacuum sensor, and all of a sudden, your car sounds like the car you select from the list. What I'm wondering is if this is an internal thing, to make the driver all happy and excited, or if you dump some big speakers in an outward facing manner, so the neighbours hear it?

More research needed, but I'm still all for the natural approach of a K&N filter and a nice chunky exhaust.

Electronic Impressionist Mimics Car Engine Sounds - Jalopnik