Bose engineers also delivered on Nissan's goal to incorporate a powerful bass unit compact enough to be mounted into the small space in the LEAF's rear cargo area. Bose implemented a 4.5-inch Nd® Richbass® woofer in a 6.2-liter custom-engineered Acoustic Waveguide bassbox. The bassbox uses patented technology applied from Bose® Wave® home entertainment products to deliver rich, low-frequency performance from a very small enclosure.For mid-high-frequency performance, the Bose Energy Efficient Series sound system includes six lightweight speakers strategically placed and acoustically tuned to reproduce music accurately, with more of the detail found in a live performance. There are two one-inch neodymium tweeters, one in each A-pillar; two 6.5-inch wide-range neodymium speakers, one in each front door; and two 5.25-inch wide-range neodymium speakers, one in each rear door. And at the heart of the sound system, a Bose energy-efficient amplifier operates on much less power and runs cooler than conventional offerings. The amplifier is also smaller and lighter because it doesn't require as many large metal cooling fins to dissipate heat. U.S. pricing for the new 2013 Nissan LEAF will start at an MSRP of $28,800 for the newly-added S grade, making it the lowest priced five-passenger electric vehicle sold in the United States. Depending on location, some consumers may purchase the vehicle for as low as $18,800 with qualifying federal and state tax credits, putting the LEAF on par with gas-powered vehicles of its size. Nissan will also continue its lease offer for the 2013 LEAF, allowing consumers to lease the electric vehicle for as low as $199 per month for 36 months, which includes tax credits and destination charges. Additions to the 2013 LEAF include: 17-inch alloy wheels and leather appointed interior on SL models, available Around View® Monitor and 7-speaker Bose® energy efficient audio system and a 6.6 kW onboard charger that significantly reduces 220V charging times and is standard on SV and SL models.