Remove dialogue from BG noise

D

DDirector

Veteran
I'm making my short film in the summer, its going to be one of my biggest projects so far, and I want to get an audio editor, but who knows if that'll happen for sure. But even if I do, I still want to know what to do.

I've seen many behind the scenes where the character(s) are talking and there is a large fan going off a few feet away. In the end there is no fan noise and its clean audio. Or hearing the director calling things out during the shot, its later removed. But, that's more simple - Its more of the BG noise.

Are there any certain things that need to be done before/during/or after shooting that needs to be done to get separated audio?

Ex. A guy is standing on the edge of a tall building. Its very windy (Using the large fans) and the actor is talking. In the end you can hear him really well, and the wind noise is very minimal.

Not just with fans, but also shooting on a very busy road. Its loud but the audio is very clear when traffic noise is supposed to be high.
Sometimes the boom op, cant even get too close to actor, and still...

I am not a sound guy, and I want to do a short with 5.1 surround sound, so I just want to know what I should be doing.
AND is there a special mic I need to be using or can the 5.1 surround sound be done from any mic? *Obviously a proper audio for filmmaking!
 
There is an art to dialog editing.

For scenes where background noise isn't an issue, you may find that lines, phrases, words, or even syllables have been replaced from other takes to cover up minor flaws (like verbal direction). But really, you should have a skilled sound person on set for your production. It's that person's job to get clean, clear dialog wherever possible, and to make sure that you have all the other building blocks (like room tone) that you need for post-production.

For scenes where loud background noise is simply unavoidable (such as your fan scenario)... that's one of the few cases where ADR is likely the only solution. Production sound's job is to get as audible a guide track as possible, and the actor(s) re-record lines in a VO booth in post-production, often reading back against video (and if desired/needed, reference audio) of the original takes. These re-recorded tracks are then finessed to make sure that all the syllables line up with the lip movements. As for the background noise you hear in the film (the wind, the traffic), that's all re-created in post.

If production dialog is recorded with heavy background noise, there's no way to separate the two in post. What's done is done, and the dialog is hosed.

DDirector said:
I am not a sound guy, and I want to do a short with 5.1 surround sound, so I just want to know what I should be doing.
AND is there a special mic I need to be using or can the 5.1 surround sound be done from any mic? *Obviously a proper audio for filmmaking!
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Hire a sound person. If at all possible, bring someone in who has the gear and knows what to do.

Surround sound is 100% a product of post-production, and even in a surround mix the dialog is mono and comes from the center channel. Using a surround-sound mic array is not going to yield you any usable dialog for your final edit, and the only things that show up in the surround channels anyway are FX (sound beds and a few other effects)... and sometimes music. Mixing your audio into a 5.1 surround mix is not something to enter into without some know-how... it's very easy to mess it up inadvertently. Again, get someone with both experience and equipment to do it properly... and only if surround is absolutely necessary to telling your story.

Dialog is recorded in mono... be it from a shotgun mic, or a lav, or a hypercardioid. And even on large productions where audio may have two booms running at the same time, and lavs on all the principle actors, those mics are each recorded to their own, discrete channels (plus a mono mix).

Here's a great post from the Audio 101 sticky that pertains to this very topic:

http://www.dvxuser.com/V6/showthread.php?172106-Key-to-making-your-film-sound-like-it-had-a-budget
 
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Most of the examples you cite are likely ADR (automated dialog replacement, i.e. re-recording the dialog in a nice quiet studio in lip-sync with the picture)
There is NO magic filter that can remove background noise. You must either reduce it adequately during shooting, or else scrap the audio track and replace it with a nice clean ADR.

To minimize the noise (and maximize the dialog recording) during shooting, this is a great summary of all the different things to be considered when selecting locations and while shooting. HIGHLY RECOMMENDED: http://filmsound.org/production-sound/openletter.htm

Also the "Audio 101" sticky at the top of this forum should be required reading.

ADR generally not for amateurs, amateur producers, or amateur actors, to I am NOT recommending it as a viable alternative for you.

I would strongly suggest simply trying to produce a good stereo mix for a few productions before attempting 5.1 One step at a time.

Here are a couple of interesting videos I came across recently...
http://www.youtube.com/watch?v=WDeGA8PL0qE
[URL="http://www.youtube.com/watch?v=8rM6jafG1b4"]http://www.youtube.com/watch?v=8rM6jafG1b4
[URL="http://www.youtube.com/watch?v=f2HKN1N2SZQ"]http://www.youtube.com/watch?v=f2HKN1N2SZQ


[/URL][/URL]
 
I agree with Richard and Alex here. A 5.1 mix on your first run is a bit ambitious. Start stereo or LCR. You will find that to be a big enough challenge to get sounding tight. Once you have a good grasp on the concept, then you take it to the next level 5.1. But jumping into that first time out, I am afraid you will not be happy with the results.

Plus, you will have a larger viewing audience for your final work, as many people don't have surround system capabilities. Youtube, Vimeo are both stereo only. Most theaters do have surround sound, but how many will show your project?

It's not about discouraging you, it's about where your abilities are right now, and what will get you the most exposure. Put it in 5.1, you won't be able to show it many places.
 
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Doc Bernard said:
Plus, you will have a larger viewing audience for your final work, as many people don't have surround system capabilities. Youtube, Vimeo are both stereo only. Most theaters do have surround sound, but how many will show your project?
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It's actually worse than that because you won't likely have the film in a format that they can play 5.1 from. They are going to be looking for Dolby Digital or possibly SDDS, and you are not going to be able to deliver either.

I will also second everyone else. There is no magic way to remove sounds from dialog. There are some things that seem like magic when they work but you won't really know IF they will work till your in post and using them. And they are not cheap AND they take a lot of time to use.

You have to be careful about taking "behind the scenes" stuff and magazine articles to seriously. For one thing filmmaking at a big budget level takes lots of people and it takes lots of time. That is generally kind of boring so articles and such tend to tart it up and make it more "magic" and less grueling late nights. The reality is a lot of long days by very experienced people.

Also with behind the scenes clips you are usually hearing the camera mounted mic for anything shot by them. Remember they are a small run and gun doc crew filming a big budget film crew. So just because it sounds horrible in the BTS shots doesn't mean that the mixer wasn't getting clean dialog for the film.
 
Noiz2 said:
Also with behind the scenes clips you are usually hearing the camera mounted mic for anything shot by them. Remember they are a small run and gun doc crew filming a big budget film crew. So just because it sounds horrible in the BTS shots doesn't mean that the mixer wasn't getting clean dialog for the film.
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Actually... speaking for myself and my colleagues, we patch in with the mixer on set as often as possible when shooting BTS.
 
The key to ADR or filtering is the same: "room tone". Get a solid 60 seconds of just the sound of the environment.

Regarding noise reduction, I've had success with two tools: The Parametric EQ and the Noise REduction filter in Soundtrack Pro. But if I must pick between the two, I take the Parametric EQ any day - great way to kind of "notch" out a particular sound. But it's hard for it not to sound "processed".

If you do ADR, do it right away or it can kill your project soooo fast. Something i've learned from more experienced people than me is to hop straight into a car with your sound guy and a recorder and boom mic and ADR that bad boy right away. Car interiors, particularly SUV's, seem to be very well designed to absorb extraneous sound. I have to mention this and if you've heard some of the ADR I have you would know why.

Thanks,
 
I'm going to move to on set ADR on my next project. We have been bringing people back in after the fact to do it in a vocal booth, but doing it on the spot seems like a much better option. Less scheduling and logistical issues and the performance fresh in their mind.
 
Zak Forsman said:
Actually... speaking for myself and my colleagues, we patch in with the mixer on set as often as possible when shooting BTS.
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Interesting. I've only done post on a handful of BTS and I could swear they were all camera mount.

Glad to hear it's not the norm.
 
gonzo_entertainment said:
I'm going to move to on set ADR on my next project. We have been bringing people back in after the fact to do it in a vocal booth, but doing it on the spot seems like a much better option. Less scheduling and logistical issues and the performance fresh in their mind.
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PRecisely. That and matching a studio to sound like it's on-location is biatch and the actors' frame of mind is easier to stay within while right after shooting the takes,
 
JoeRawlins said:
PRecisely. That and matching a studio to sound like it's on-location is biatch and the actors' frame of mind is easier to stay within while right after shooting the takes,
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The only problem is the same factors that screwed up the production audio to begin with - wind, background noises, etc - are likely to still be present on the set when you try to record ADR lines there. Plus the actor needs to see his performance so he can speak his lines in perfect lipsync to the picture, something hard to do in the field
 
DDirector said:
I am not a sound guy, and I want to do a short with 5.1 surround sound, so I just want to know what I should be doing.
AND is there a special mic I need to be using or can the 5.1 surround sound be done from any mic? *Obviously a proper audio for filmmaking!
Click to expand...

Recently watched "Midnight in Paris"(2011). Woody Allen uses mono-sound, and for many of the shots, almost master shot, and long takes. All of which are somewhat contrary to current popular techniques. While I'm not a fan of Allen's work in the sense of story, I can appreciate the 'cheap' production, which in the viewing does not lend to 'cheap production values'.
 
If you need to do ADR: be sure to direct your actors too... If during the shoot they were suffering and having it difficult (because of emotional dialogues or so)...Well...they'll have to
redo that during the ADR... Otherwise it will sound as "reading".

And I also would start with a "simple" 2.0 sound (stereo) sound.
 
I usually like to do ADR in my vehicle, right at the scene. I use a crude method of what window to close or leave open. I can park at the desire distance to achieve my background sound or ambiance. It might sound elementary but it works for me.
 
dre83 said:
If you need to do ADR: be sure to direct your actors too... If during the shoot they were suffering and having it difficult (because of emotional dialogues or so)...Well...they'll have to
redo that during the ADR... Otherwise it will sound as "reading".

And I also would start with a "simple" 2.0 sound (stereo) sound.
Click to expand...

I'm currently on a film right now where the director spent 4 days recording ADR only to say a couple months later "I actually don't like the ADR.. can you just fix the production sound?" Wish it was that easy.
 
Steve House said:
The only problem is the same factors that screwed up the production audio to begin with - wind, background noises, etc - are likely to still be present on the set when you try to record ADR lines there. Plus the actor needs to see his performance so he can speak his lines in perfect lipsync to the picture, something hard to do in the field
Click to expand...

Naturally, removing to a car or a motor home or simply further down the road is ideal. In my experience, making the line lip sync by the actor following along visually can be just as frustrating as just recording it on-scene and then making it match as best as possible in post. The fact that the actors have just done the lines on-set is close enough for me. Then, repeating it one more time for sound isn't a big deal and they're in-the-moment.
 
Sometimes I do "WILD LINES" (ADR on set) when there's a fan turning that has to turn (wind effect) or a smoke machine or I can't reach it. So in short: disturbing sounds that are needed for the shoot but can be switched off.

In that case, the actors are in "there zone", and can perfectly do the same (little time stretch maybe in post for accurate lipsync).

But when doing ADR, the actors have done other projects, other characters...So they have to get back in to what they were... It needs some practice (also from the actors itselfs). Not everyone has done ADR, so when it's there first time...Well..it's like first time driving, first time swimming, first time doing DOP, first time doing sound on set... They also have to learn.
 
ryanjf said:
I'm currently on a film right now where the director spent 4 days recording ADR only to say a couple months later "I actually don't like the ADR.. can you just fix the production sound?" Wish it was that easy.
Click to expand...

I hope this project of yours is not what I think it is! Harsh.
 
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