Yeah, here's the thing - I also wanted to be able to use live audio from a microphone with the vocoder in FL, but as far as I can tell it's just not possible.
There's just no implementation for such a thing.
you couldn't send microphone audio as MIDI data as one problem, but there's no sort of plugin to take in audio from your microphone input jack and use that as an instrument track in FL, to be used for live vocoding.
There's two possibilties: 1.) Nobody had the insight to think of, or the capability to make, a plugin that let you use incomming audio as an instrument track.... if this is the case, then someone, please make this, it would be awesome! or 2.) Maybe live audio is just plain impossible with the way FL
studio works, having to process things and all as it does.... MIDI gets away with being more 'live' in FL I suspect because it's electronically synched, but live audio might be more of a challange for FL to run properly so that is perhaps why there's no functionality for that.
But if anyone knows of a way to make this possible and prove me wrong - it'd be much appreciated, as FL studio's vocoder is very handy and i'd like to be able to use it live.
however, if you want to use the vocoder just in general, you can record audio, and import it as an audio clip or sample and set that track as one of the vocoder's channels. There's a tutorial somewhere in FL on setting it up if you poke around enough, and also a pre-made template too.