Bifrost USB Digital Analog Convertor Inputs: Coaxial SPDIF, Optical SPDIF, USB Input Capability: up to 24/192 for all inputs Output: Dual RCA (single-ended) Power supply: 5 stages of regulation, including separate supplies for digital and analog circuits. Upgradability: Separate, modular USB Input Card and DAC/Analog Card are snap-in replaceable