Hi @kylarleds,
The input jack takes line-level audio. Thats the level that would be fed to speakers or headphones. Microphone-level audio is something like 1/1000th as strong.
You can totally use a external mic, but you’ll need a preamp to bring it up to line-level.
The idea with the aux input is that it can be fed from a stereo or output from a DJ setup so that you get a clean input without ambient noise.
I hope that helps! We’d love to know what you end up doing with it