The NAC-N 172 XS defines a creative point at which two worlds collide – the traditional world of separate pre and power amplifiers, and the new world of network streaming.
For a start, the NAC-N 172 XS is a very high performance and inherently musical preamplifier. It combines a mix of analogue and digital audio inputs, a digitally-controlled analogue volume control, and analogue outputs to connect to a power amplifier. And it offers even more besides, because along with its conventional inputs it includes a front panel USB audio interface and a wired or wireless network connection to access internet radio stations, stream from UPnP music servers and streaming millions of songs with Spotify Connect and TIDAL lossless audio streaming.
More info here