The owner of this BMW 745i wanted to improve the quality of sound in his door speakers and find a way to hook his phone up to his radio. A simple solution for this problem was the Kenwood Excelon KAC-M1824BT amplifier. This will amp up the speakers to make sure they are adequately powered so they can produce quality sound and the amplifier is Bluetooth enabled so he can stream all of his music wirelessly. He can also control it from his phone or the controller that was mounted for the amp. This was a very happy man at the end of the day and was glad he went to see the experts at Audio Express.