This dac uses eight pcm1704u-k 24-bit r2r chips to convert usb digital audio into analogue signals without oversampling or filtering the data. these are regarded as the best sounding r2r chips and are still in use in high end converters like naim's statement spec nd555 streamer. the usb input is the sole input and single ended analogue out sent via xlr connectors. the analogue outputs are at full signal at a voltage of 1.5v and the output impedance is 33ohms. usb audio can be played back from phasure's proprietary xxhe software or any third party using kernel streaming and running on pc with windows 7...