The ART USBDI takes in USB audio, converts it to analog audio and then isolates the output using custom transformers. The output isolation is key to removing ground loops and other system noise between the digital and analog audio systems. A large knob on the USBDI front panel allows quick, precise control over the output level, while a separate headphone output allows the user to monitor the system. The front panel Main Outputs switch allows the user to keep the isolated outputs at a fixed level while controlling level of the headphones output. The line level XLR outputs are available for connecting to all sorts of systems. The Main outputs are always isolated but allow the user to control the ground reference to reduce noise. The USBDI is powered by USB, drawing less than 200mA and eliminating the need for an external power source.