Alpha USB

About the Alpha USB

The Berkeley Audio Design Alpha USB is an external asynchronous USB-to-digital interface, not a DAC or analog audio device. It accepts USB Audio 2.0 High Speed audio from a computer or music server, electrically and galvanically isolates the USB/input section from the digital-output section, reclocks the signal using separate precision oscillators for the 44.1 kHz and 48 kHz sample-rate families, and provides a switch-selectable 75-ohm coaxial S/PDIF output or 110-ohm balanced AES/EBU output. The original Alpha USB is distinct from the later Alpha USB Series 2 and Alpha USB Reference Series models. Berkeley Audio Design currently lists those newer models rather than the original Alpha USB, so the original model should be regarded as no longer manufactured and replaced by newer variants.