What is the role of an amplifier? Class AB vs Class D amplifiers. How much power do you really need? How do get the synergy between your speakers and amplifier right? Questions answered! The Fiio Taishan D03K DAC mentioned in this video only has coaxial and optical digital inputs. The mini usb input is for power purposes only. If you need a usb input, you should choose another DAC. Sorry, I didn’t mean to mislead anybody.