Take a look at the BMW M2 Tested with and without Active Sound Design. ASD amplifies the sound the engine through the speakers.
[video=youtube;IMUV2u4Bp0A]https://www.youtube.com/watch?v=IMUV2u4Bp0A[/video]
[video=youtube;--3p20D5yH8]https://www.youtube.com/watch?v=--3p20D5yH8[/video]
