The Elektor Car Booster 10/1994 is an excellent audio amplifier with outstanding features. Unfortunately, the Car Booster was developed only for use in vehicles. There for a special switching power supply was necessary to increase the 12V on-board voltage. In this project, a new 230V power supply was developed, the protection circuits was revised also small changes to the amplifier. The result is a excellent amplifier with a phenomenal sound.