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In recent years, the ANC technology was adapted for intake and exhaust systems on several passenger vehicles with a variety of diesel and gasoline engines. In these predevelopment activities, the active components (actuators, electronic hardware and software) were rigorously improved and its durability professionally validated leading to an increased system performance even under very harsh conditions. Depending on the customer targets, this yielded several benefits when compared to conventional exhausts. For example, a passive conventional dual exhaust system of a highly efficient 4-cylinder gasoline engine could be replaced by an active single exhaust line without compromising on the acoustic targets but saving a considerably amount of design space and weight. In particular, the space advantage can be utilized to create innovative exhaust layouts. To support future downsizing of engines, for example, an ultra-compact exhaust layout is proposed.

In the past years Eberspaecher has installed Active Exhaust Silencers on several passenger vehicles with different diesel and gasoline engines on a prototype level. Meanwhile, a substantial reduction of the exhaust noise is regularly achieved in a broad frequency range covering all relevant engine orders. Due to the higher acoustic excitation and higher exhaust temperatures in gasoline engines it is more difficult to implement the ANC-technology on those engines. However, results from roller test benches focus on the acoustic performance as well as weight and volume reductions and demonstrate a marked improvement which was achieved with gasoline engines too. Further progress was made in the development of the durability and industrialization of all relevant components of the system. Finally, current design trends and possible fields of application will be discussed.