Will the OctoPre MkII supply phantom power to my microphone?

Yes, the two phantom power switches on the front panel turn on +48V phantom power to Mic inputs 1-4 and 5-8 separately. Phantom power is only sent to the XLR connectors on the combo input, so if a group of 4 preamps is used for both microphones (XLR) and line level sources (Jack cables), +48V is only sent to the microphones.