section_path: Performance/Sound levels
section_name: Sound levels
paragraph_text: Sound levels
  
  Vehicle noise is predominantly from the engine at low vehicle speeds and from tires and the air flowing past the vehicle at higher speeds. Electric motors are quieter than internal combustion engines. Thrust-producing engines, such as turbofans, turbojets and rockets emit the greatest amount of noise due to the way their thrust-producing, high-velocity exhaust streams interact with the surrounding stationary air.Noise reduction technology includes intake and exhaust system mufflers (silencers) on gasoline and diesel engines and noise attenuation liners in turbofan inlets.