Does the Korg d1600 have mic preamp or d/a converters inside that would allow me to use this piece of equipment as an audio/midi interface? I believe It has all the appropriate inputs and outputs?
The Korg D1600 has a comprehensive list of inputs, including mic preamps with phantom power. But I see no mention in the manual (linked below) of being able to use it as a computer interface. The words 'USB' or even 'Firewire' do not appear in the manual. So I'm afraid your answer is no. It is essentially a self-contained recorder.