HiFi Specification and general guidance


I’m new to Volumio, having only downloaded it tonight but it looks very promising. My first question is;

I am undertaking a project as part of a HND course and im looking to develop a Wireless Music system using the Raspberry PI has the main I/F. I will be using a DAC to utilise the digital I2S outputs and will be feeding into a amp and onto 2 drivers with a frequency response of 20Hz to 20kHz, with a cross over at around 2kHz. Can anyone advise as to what constitutes HiFi? I need some specifications on which to test against so that I can prove that I meet a reasonable ‘audio’. I appreciate that HiFi can be very subjective but BER, SNR and frequency response would be a good place to start?

Secondly; if I’m using Volumio, do I need something like AirPlay or Tuneblade to output from my PC to a PI device over WiFi? I don’t think I do, but not having much luck currently in pointing Volumio to my music directory.