Teac AH01-S Stereo Amplifier with D/A Converter B&O ICEpower Stereo Amplifier with BurrBrown 32bit/192kHz DAC (PCM5102) USB Audio Interface for High-resolution audio file from PC/Mac Digital Audio Inputs for Digital Audio Sources Binding-post Speaker Terminals and Subwoofer Preout, AH01-S works only with 120V USB Audio Input: High-speed (USB2.0) USB Audio Transfer Mode: Asynchronous Mode