Bristol - and everyone else who's interested

- you are absolutely right, what I and many others wrote here is a very clinical way to do it. In spoken words, voice overs, voice acting etc, this is actually crucial. I do this for a living and when we leave a breath in it's usually to add to the acting. For narration voices we often leave the breathing within the sentences
if they sound nice. If not, we cut it out and delete it. For all other voice over work we remove everything unless it is breathing we want (gasps, exhausted etc).
The reason is, breathing and everything else that may come into the silent parts of audio like creaking chairs, shoes tapping on the chair, lips smacking, hands brushing a sillk shirt or track suit pants, they are all just adding noise. And whenever I've heard it left in I cringe over the poor surgery - so to speak. Voice over work is usualy done for a sound palette where there's left room in the mix for dialogue or narration, like documentaries, voice overs, commercials, films, computer cames etc and all these little sounds the actor makes becomes extremely audible. And that's because - in layman's terms

- a microphone have much better hearing than us humans.
So, when doing this type of editing, entering envolope dips or highlight select, menu and mute will take a long time and the risk of having half breaths or small lip sounds at the end or begining of a clip coming through is increasingly high. Sure, this is fine for music and I do it all the time for that, because here the voice is packed into a mix and all these sounds simply drowns within it all. However, this would actually be counter productive in voice acting, ADR, voice over work etc. The interesting thing about the human voice is that we are only able to make one sound at the time; breathing or speaking. Unless some mechanical noise like lip smacks, tounge slaps, mucus are caught in the audio forcing a re-record or a surgical edit in an audio editor in the edit stage, a breath and other noises are extremely easy to spot in the audio waveform and geting rid of it is a matter of left click+drag and hit Delete. Most voice actors will sit or stand very still when performing and move their bodies when breathing and this doesn't sound good when the characters on screen are not doing anything that these sounds are related to. And if you're listening to an audio book or simmilar, hearing all these sounds are severly distracting for the listener. And when this is played on a 35000W cinema PA system, each and every one of these little sounds get EXTREMELY loud! If they are present in your iPod ear buds, they get extremely close. And de-essing too much and massive EQ work will probably deteriorate the audio in the end and make the voice talent sound like a muffled lisp. Not adviceable.
So what to do then? Well, like I said, delete it all and throw it in the bin. And by doing so it's way easier to adjust both timing of the spoken/read parts or the sync to a picture because everything will be freely moveable without moving everything else. This I can promise you will appreciate when try this kind of work the first time and pretty much eliminates everything that involves envelopes and muting of audio in a biger clips - like the OP have discovered. But the point made about the digital silence is indeed valid but there are ways to remedy this.
For voice overs like documentaries and such, there are none. If your room is so alive that you can hear ambience being cut off then you should start looking at how it all is recorded. You'd have to do it again. If this for some reason is not an option, then perhaps a little room reverb added can smooth it out. It works, but it ain't pretty. Most recordings in the narration style is completely dry as if the speaker was siting next to you and the only ambience you want is the same that you are siting in your self, when it comes from the TV. When doing this for picture, either in a cartoon, motion picture, computer game etc, effects are always added to place the voice in a room that matches what the audience can see. So that happens automatically so to speak. It is very rare that voices in these scenarious are completely dry when mixed but if they are, it's because the character on screen is outside - and outside, no one can hear you breathe unless you're really close to them, because of the lack of reflective surfaces on four sides which is the reason for why we can hear other people breathe indoors. For example. And even then it's not that noticeable. However, a voice over in a song, like poetry, a speech and the like, you add the needed reverberance to it like you would any other instrument, to make it sound good. If it's good dry, then that's how it sounds good
OK, this got a bit long but I hope this gives people some ideas to work with these type of recordings. Voice over work and dubbing is quite different from working with sung vocals, especially in a musical track. But in the end, you need to find a way that works for you to get the results you want. The only important thing in the end is how it sounds and if done to picture, how it looks as well. If it's not convincing it's usually rubbish.
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