Partial bans on motor vehicles from urban areas have been shown to have minimal impacts upon reducing sound levels (as would become clear from later modeling studies); for example, the partial ban in Gothenburg, Sweden resulted in minuscule reduction of sound levels [REF].
Regulation in the EU and Japan of tire and power-train noise has only sought to reduce noise by approx 3 dB, and will only slowly take effect because a few older noisier vehicles can dominate the soundscape.