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 "excuse me" sound than "hey you" sound whenever you want to warn people you're approaching. Of course, depending on the driver does have its limitations, and Chevy says that future iterations of the Volt are likely to incorporate a more active system that can automatically alert pedestrians. Check it out in action after the break.