Toyota will be offering its Japanese customers an optional (for now) $150 device that makes its 3rd generation Prius hybrid easier to hear at low speeds. They call it the "Approaching Vehicle Audible System", and it basically makes whirring sounds that vary in pitch with the speed of the car up to 25 kph (check out the video below).The Problem
Most of the time, the noise that a car makes comes mostly from the tires on the pavement, not the engine. But at very low speed (under 15 miles per hour), the tires become much quieter and engine noise makes a difference. It's not a huge problem, unlike what some anti-hybrid people claim, but it's worth mitigating. That's the thinking behind this device and others like it.
Based on this video, it seems like a pretty annoying noise and I can't imagine what a bunch of Priuses would sound like stuck in stop-and-go traffic. But maybe the video makes it seem worse than it is.
I think it's a great idea to make hybrids and electric cars a bit safer by having them emit a bit more noise in certain specific conditions, but I also think it would pay to go back to the drawing board and find a sound that is more neutral and pleasant. This is especially important to get right because in a few years there will be a lot more hybrids, plug-in hybrids, and electric cars on the roads, and we don't want to cause a backlash of Vuvuzela proportions.
Might Come to the U.S.
The Toyota device is designed to "meet new Japanese Ministry of Land, Infrastructure, Transport, and Tourism guidelines for hybrid and other near-silent vehicles," and Toyota is considering offering it in the US at some point in the future.
Via AP, Prius Chat
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