The perverse trend of noisy hybrids

TOKYO -- How’s this for a perverse trend? Modern technology has made cars so silent that automakers are now adding fake sounds to make them noisier.

The Nissan Leaf electric vehicle was the first to add a digital humming noise to warn people with hearing or vision impairments that the car was coming.

Now the Toyota Prius is following suit.

Toyota offered this week to hook up a speaker in the engine compartment of the popular hybrid to broadcast a synthesized sound, so pedestrians can hear it approach in electric-only mode. Listening to a video of the device in operation brought to mind a chorus of cicadas.

The option is being offered only in Japan. But Toyota is studying it for the United States.

The catch: The dealer-installed option costs about $150.

It used to be that car companies wanted to make cars as quiet as possible. Now they are charging customers to make them louder. And all in the name of safety.

Toyota points out that the sound isn’t required by law. But if safety is really the name of the game, it seems Toyota ought to make the device standard as is done in the Leaf.