Here is the best way to itemize your audio tracks so that you are able to insert new audio in the correct location.
We Gotta Get Organized
Organization in non-linear editing software like Final Cut Pro does not just apply to the media management aspect of it or correct cataloging but also in the intricate parts of the actual editing project. The timeline itself, the building plot for your eventual film creation, needs to be an ordered place so that you have the ability to continue creating in a productive way. The way Final Cut Pro is fashioned, and many other professional non-linear editing suites, is for there to be a large number of video and audio tracks. This way you can layer a large number of different ones on top of each other, letting them combine at spots, and having the ability to know exactly where everything is when trying to cut around. Though you may have to use multiple blocks of similar media at the same time it is best to keep each specific type of both video and audio on separate tracks for easy reference and organization. There are often layers of the same type of video track occurring and it takes a more thoughtful approach to organizing them, but audio needs to maintain a basic structure for most types of film editing. Since there are a standard number of audio tracks that are normally used there is a clear way to keep these tracks organized when editing your film in Final Cut Pro.
There are essentially five main audio tracks that are used in standard film editing. The voice over if there is one is put on to the very first two channels because this ends up being the most central, basic, and clearest audio track in the entire film. The stereo audio of a video taped scene is usually always on two separate channels. If there is none then all the other tracks can get bumped down another track number. The next channel is where the dialogue or scene audio goes. This means that all the audio that is intended from within the story space that is filmed as part of the location scene is here. This means mainly the dialogue, but also the sounds of things that occurred in that scene that were captured along with the dialogue. The next channel is where you begin adding the sound effects that were recorded later, such as ones you recorded yourself or purchased from a sound effects recording house. The fifth channel is then for the music, which comes in and out depending on the scene. If this pattern is maintained then you will always know what goes where at different times.
This is especially important for cutting together different clips of coverage of the same scene so that you know exactly where to cut to maintain the same beat in the dialogue and scene motion. One of the most important parts of filling the gaps is using room tone or environmental noise, and you may want to designate a new track for this. You can end up putting this on the same track as the dialogue, but it is better if you don’t just use it in between audio clips. It is meant to fill the gap but it is better if you go ahead and let it overlap onto where the dialogue audio comes in so that it sounds smoother. The whole purpose of that environmental sound is to fill those rough spots as well as to use it to remove noise in your audio mixing software.
The other tracks can be used for other things, such as possible commentary or foreign language dubbing. Usually dubbing will end up requiring splitting channels, but recording it and then placing it on an open channel is easier. Thankfully Final Cut Pro offers an almost unlimited number of audio channels, though it is not recommended to go more than a few.