Found out last week my Mini-DAC's gain was set *way* high. Sonic effect: harshness in upper mids, congestion, little play in the preamp's volume control. Got this advice: if you are using a tube preamp you may be able to work with a higher gain setting than the conventional input level of around 2 volts. A solid-state preamp could overload if your DAC's output level is too high.
