NOTE: This product is not compatible with the Harmon Kardon system *Only for BMWs with factory S676A Hi-Fi systems* BimmerTech Premium Audio System (BMW Amplifier upgrade) Features Exclusively sound upgrade Pre-programming and optimization specifically for BMWs and your musical preferences Higher Signal-to-noise ratio and a much higher output power than regular OEM unit Plug & Play install for BMWs and MINIs with our without a factory amplifier (cars that lack it get equipped with additional harnesses and brackets) 2-year limited warranty Technology Proprietary Class HD Technology for peerless sensitivity and minimal heat generation 8 separate configurable amplifier channels for maximum flexibility PExtremely powerful DSP with virtually limitless sound adjustment options freely configurable via PC- Tool software (Windows) 56-bit DSP technology and 24-bit AD/DA converter from BurrBrown Design Start/stop capable down to 6 volts supply voltage The latest D/A converter-controlled P3S power supply technology with "ECO Mode" State-of-the-art SMD technology for a more compact design and maximum reliability Six-layer printed circuit boards in multilayer technology for the best possible power and signal transmission Inputs/Outputs Optical S/PDIF input 6 – 192 kHz with an integrated sample rate converter USB-on-board for direct connection to a PC Freely configurable 2-channel PreOut for the connection of additional amplifiers Plug jack for optional cable remote control, functionality configurable via PC software DIY Instructions: