Why not use another program to record audio? What's the difference?
Yes, it's two apps to manage instead of just one, which is probably what you're going for, but there's a pretty big and early jump in mindset as you get into media-related stuff.
- There's the, "Trust us, it works." level, which does work as long as you only want / need to do what they've already designated for you to do.
- And there's the, "Here's a pile of tools, have fun building your own rig!" level, which allows you to do anything and everything in any way that you want, need, choose, etc. But you're expected to know all of how it works and how to troubleshoot it. Or stumble around on forums, stub your toes on your own shoes for a while, and eventually get to where you have that knowledge. ;-)
- Not much middle ground.
The reason for such a big jump so early is that media is inherently complicated, technical, and creatively unique to each individual person that uses it. If the creativity can be constrained away, then a well-polished app can be made to do exactly that. But as soon as you have something that supports creativity, those creatives must also be technical enough to manage that side of the endeavor as well.
Given the environment, OBS has done a WONDERFUL job, I think, of spanning that gap already.
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Anyway, one way you might do it, is to:
- Record video like usual with OBS, which gives a single file with everything in it.
- Import the video file into Audacity, which ignores the video information and only imports the soundtrack(s).
- Work with it like any other audio.
- Export a new audio file.
- Load the original video file and the new soundtrack into a video editor.
- Line them up. (they should still be the same length, so snapping to start and/or end points *should* be enough)
- Mute the original video.
- Export a new video file from the editor.
Audacity needs its FFMPEG plugin in order to do that - to read the video file and get the soundtrack from it. It's not preinstalled or built-in for licensing reasons, but it's easy to install yourself, and then it "just works".
You might as well get the MP3 plugin too, while you're doing that process anyway. Same deal there.
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Or, to do it all in one shot, you might use the Noise Suppressor filter in OBS.
The risk to recording processed like that, instead of recording raw, is that you're stuck with whatever processing you recorded. You can't remove it. You might compensate for it, with varying degrees of success, but it's generally better to record as raw as you can get and do your processing later, until you find that you've been using the exact same processing for a while and don't see it changing. *Then* you can record after that processing and save a few steps.
