YES! Ensemble's preamps (found on channels 1-4) can be bypassed if you'd like to connect a line level input source such as an external microphone preamp or mixer. Here are the two things you'll need to do: 1) Connect the devices line level output to Ensemble's XLR input jack. 2) Go to the input tab in Maestro 2 (found in your Applications folder) and change the input selection from "Mic" to "+4 dBu" or "-10 dBV". The line level selection will depend on the type of gear you're connecting. Professional audio equipment most often uses +4 dBu, while consumer audio gear is set to -10 dBV.