Ridiculously simple audio editing question for Garage Band

Question

Ok, so this is really a fundamental
question. It concerns editing technique.
In analog mixing, the editor put
the sounds to be saved in the right
places on each of several tracks --
narration, sound effects, lip sync,
music, etc. The tracks were then
all locked together and the mixer
adjusted the volumes to either save
or reject audio information.
A blank master received the information
and that was your final product,
in sync, sprocket by sprocket, with
the video.
My question, then, is, how do you
do it in digital multitrack such as
Garage Band? Are you aiming to have
4 or 5 tracks all level controlled
or do you simple erase unwanted
sound, or what exactly do you do,
in post production? If you are going
to do a voice over, then you have to
do a mix at some point, not just a
cut and paste. What's the philosophy,
if you don't mind my asking?
Thanks,
Ed

Answer 1

Wow... you gave me flashbacks to a movie soundtrack I scored, with separate reels of tape all synced up and whirling away for final mixdown!
To answer your question as best I can in a paragraph or two, digital mixing is unlimited compared to analog. Whereas tape has a physical limit, you can always add another digital track (there are limitations to digital, but they are becoming harder to reach as systems become increasingly powerful). So no need to erase. Editing is also a breeze. Digital tracks are endlessly malleable, with virtually every parameter available for automation.
Sometimes you might mix down to stems or mix everything down to a stereo master (or alternative mixes) for post production. Similarly, in post, they can deal with huge numbers of digital tracks from different sources.
In terms of a professional workflow, Logic is the more typical choice over Garageband, and includes a number of features designed for scoring to picture: variable sample rates, frame rates, etc.
Gain staging in digital recording is different than in analog, and it requires a different approach to achieve excellent sounding results. But the digital workflow is so much more flexible, forgiving, and economical, that it has been the death-knell for the analog workflow. Infinite bussing, routing, mixing, comping, storing, stemming... infinite possibilities, really!