The AU-D1D is a Dolby Digital to Analogue audio converter (DAC) which allows the user to easily convert digital Optical signals to analogue L/R Stereo for connection to any AV receiver. With audio sampling rate support up to 48 kHz (Dolby Digital)/96 kHz (LPCM) and I/O data rate support up to 24-bit, the AU-D1D provides high quality sound conversion. The Dolby Digital Decoder function guarantees that Dolby digital audio signals are downmixed to analogue stereo without loss of quality.This device is perfect for use in digital recording systems, computer audio systems or digital mixing consoles and is powered from any USB port allowing it to be used with USB equipped HDTVs, Blu-ray players or computers without the need for a separate power supply. With many of the latest generation of HDTV's now only providing an optical audio output, the AU-D1D allows the user to easily integrate the digital audio signal into their AV receiver.