What device lowers the noise created by the exhaust of an internal combustion engine?

In most internal combustion engines, mufflers are located towards the end of the exhaust system. The muffler is designed as an acoustic device to lower the volume of the engine's sound pressure by acoustic quieting. However, this noise reduction is unavoidably accompanied by the limitation of exhaust gas flow, which produces back pressure and may reduce engine efficiency.

Asked by Vasilii Kulev · Last updated 3 years ago · 10.1K views · SOURCE