http://www.autoevolution.com/news/nissa ... 21303.html
Also here: http://blogs.edmunds.com/greencaradviso ... odels.htmlAside for the Leaf itself, Nissan will showcase the Approaching Vehicle Sound for Pedestrians, which will be first featured on the Nissan Fuga hybrid this fall. The sine-wave sound system sweeps from 2.5kHz at the high end to a low of 600Hz. The sound emitted by the system is louder when the car starts, it is released as an intermittent sound when the car is in reverse and is disengaged when the Leaf exceeds 30 km/h (18 mph).
And here: http://finchannel.com/news_flash/Oil_%2 ... xperience/Nissan said in a press release late Thursday that the sound system "will make sweeping, high-low sounds" that will be loudest when the car is started and will be generated intermittently when it is backing up.
The EV sounds are generated by a synthesizer located in the dash and broadcast via a loudspeaker in the front of the car (the engine compartment on a conventionally powered vehicle).
Depending on the speed and status (accelerating or decelerating) of Nissan LEAF, the sound system will make sweeping, high-low sounds. For instance, when Nissan LEAF is started, the sound will be louder, so a visually impaired person would be aware that a nearby car was beginning operations. And when a car is in reverse, the system will generate an intermittent sound. The sound system ceases operation when Nissan LEAF tops 30km/h and enters a sound range where regular road noise is high. It engages again as Nissan LEAF slows to under 25km/h.
The system is controlled through a computer and synthesizer in the dash panel, and the sound is delivered through a speaker in the engine compartment. A switch inside the vehicle can turn off sounds temporarily. The system automatically resets to "On" at the next ignition cycle.