I have an audio cd that is 8 bit music, and I can rip it to my pc in .WAV format. I have seen the SD shields, and I think that would be a good place to put the audio file since the arduino memory is so small. I was hoping to be able to have the audio input over a serial connection from the pc. This is also just a first attempt at this project. The audio codec shields and DAC shields would probably work perfectly, but I was hoping to figure out how a high end DAC works and implement a simple one of my own.