Harman says it has been awarded a contract from Fiat Chrysler Automobiles (FCA) to equip Fiat Chrysler vehicles with Engine Order Cancellation (EOC) technology, which decreases perceptible cabin noise.

EOC is part of Harman’s “HALOsonic” product suite of ‘active noise management solutions’ to reduce noise and enhance sound inside and outside the vehicle. The company said it will be installed in ‘numerous Fiat Chrysler vehicle models’.

EOC uses active noise cancellation technology to reduce the drone and rumble induced by the engine vibrations in the car cabin. It uses engine RPM signal as a reference to generate a sound wave opposite in phase to the engine induced low frequency noise. Error microphones mounted in the roof of the car provide adaptive feedback on the cabin noise level in order to fine-tune the cancellation.

By decreasing perceptible cabin noise, EOC enables automakers to pursue various measures to reduce vehicle weight as part of the move to improve fuel efficiency without impacting in-cabin noise.