HQPlayer can perform some very complex and computationally expensive audio processing. A desktop computer will have a lot more computational power and memory resources for this than an embedded device. The resulting data can then be output to a DAC connected directly to the digital output of the computer, or to an NAA (Network Audio Adapter) endpoint which itself may be a DAC or could output the data over digital to a separate DAC.
I don't think there are a lot of NAA endpoint audio devices out there, but I'm not super familiar with the topic either. I think the majority of people have their DAC connected directly to their HQPlayer server.