Within the Harman group, there is a large department for automobile acoustics besides the Home HiFi and mobile entertainment part. This department has developed the Harman Individual Sound Zones, which are revolutionizing car audio. There is no need for every passenger to enjoy the same music as the driver, because besides the entertainment system for the whole car there are individual loudspeakers for each passenger in the headrest and the roof liner. Everyone can enjoy their own music; signal processors make sure that the concurring programs from the other seats as well as noises from outside are mostly faded out. In addition, every passenger can fine tune within the system, in case he still hears too much from the others. Nevertheless, the driver receives all warning signals from the outside as well as all announcements from the navigation system.