[kittonian]

It is impossible to have a plug-in act as a mic-pre because in order to get the signal into the computer you have to go through a converter which accepts line level inputs and outputs that line level signal to digital. How are you possibly going to amplify a mic-level signal when you have no mic-level signal to amplify? Plus, the amount of signal going into the converter would be so low and noisy you'd never want to use it in a recording.

Other "plug-in amplification" software that is available is really just a modeling of gain on a pre-recorded signal. You can model EQ, Compression, Reverb, etc. but if you are going to be using microphones, you absolutely have to have a mic-pre to get that signal into your converter and thus into your computer.