Naturally, the 2014 Cadillac ELR’s interior is silent when running on battery power. The luxury coupe’s engineers went to great lengths to keep it that way when the range-extending generator kicks in.

ELR uses active noise cancelling, a technology that samples noise and generates a sound wave with the same amplitude but with inverted phase, which cancels out the unwanted noise. The ELR’s system electronically gathers input from the vehicle’s generator and powertrain, as well as from three ceiling-mounted microphones, and delivers an appropriate noise-cancelling signal through the Bose audio system.

“Acoustic refinement is an important attribute of every Cadillac interior, and ELR is no exception,” said Chris Thomason, ELR vehicle chief engineer. “Considering how quiet the car is during pure-electric driving we knew the generator sound had to be as pleasant as possible, and we were able to achieve it with active noise cancelling.”

Active noise cancellation reduced the need for traditional sound-deadening materials, but ELR does use a variety of sound-buffering and -absorbing materials to minimize wind, road and engine noise, including: an acoustically laminated windshield; sound deadener applied to the floor pan, trunk and roof; triple-sealed doors with acoustic perimeter water deflectors; acoustic foam baffles inside body cavities; and an isolated front suspension cradle with hydraulic powertrain mounts to isolate road and engine vibration.

ELR will be available nationwide in the US beginning in January 2014.

Source: GM