Whether it's voluntary or enforced, it seems to be a safe bet that most electric vehicles will eventually break their silence in one way or another to warn nearby pedestrians -- especially the blind. Chevrolet looks to be taking a slightly different approach than most with the Volt, however, and it recently tested out its system with a group of visually-impaired folks at its Milford Proving Grounds. Rather than simply making the vehicle sound like a regular car, Chevy has implemented a driver-activated system that emits what's described as more of an
