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ccsnd

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As I see it hot is good in the field bot when coming into a room it's all different there.

Different rooms have different gear in them, the size of the mix room changes your mix so having a lvl set to a standard it's problematic for me.

I think it all comes to the final compression of your mix, most of the time if it is a film it needs a mix for teatheres that not always sound good for a tv compressed mix. So it's all has to fit in the box. When u mix count on your ears bot don't forget you have to put it in a tape or a reel or DVD and they trick is to get the right fit to the box. That when you hear it it will be sweet.

Glad to know if there are final mix compression recomondations to mix.

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Any producer doing a show that will use a lot of different soundies (happens all the time) should have a tech spec doc that they send to people who haven't worked their show before ahead of time. I've helped draft a lot of these docs for producers in my area before they went on the road. It doesn't avoid all problems but it avoids a lot of them. Average levels can be part of this doc, as well as TC, SR, file naming conventions, channel assignment, micing technique, delivery method etc etc.

phil p

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I always liked the idea of sending sample files to post before actual production (time permitting, obviously.) On one show I did, there was a really high level of communication between myself and the post team (way more than usual or expected)... and my sample files were approved before we ever started principle... it set a great standard against which I could gauge my production tracks, and really made things easier from the start, carrying throughout my time on the production. Obviously this isn't always possible, but it really helped me settle in and concentrate on the other aspects of the job.

~tt

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Any producer doing a show that will use a lot of different soundies (happens all the time) should have a tech spec doc that they send to people who haven't worked their show before ahead of time. I've helped draft a lot of these docs for producers in my area before they went on the road. It doesn't avoid all problems but it avoids a lot of them. Average levels can be part of this doc, as well as TC, SR, file naming conventions, channel assignment, micing technique, delivery method etc etc.

phil p

Doubt it's yours, but what a gem:

"PRODUCTION AUDIO GUIDELINES

MIC PLACEMENT:

MICS SHOULD ALWAYS BE POSITIONED FOR THE BEST AUDIO (tightest, most direct sound) centered is usually best unless you know that the subject will be facing a particular direction the ENTIRE scene… if there is any question - keep it centered, high and tight.

We prefer if the mics were hidden. If this is not optimum for the cleanest audio (due to fabric noise, chest hair, etc), then you may expose the mics.

Note: Do not use large, fuzzy windscreens(i.e. Micro Cat, Baby Koala) except in EXTREME conditions. If you absolutely must use these, then make sure they are not prominent in the scene or hidden entirely without compromising your audio.

The mic packs must ALWAYS be hidden.

MICS should not be removed or repositioned unless the subjects clothing has changed… levels should be set BEFORE shooting and should not be adjusted during filming for any reason. If you have to make a slight tweak, do it between takes. If any major adjustment is needed/made, please let the field producer know as they may want to do another take to ensure levels match with the rest of the shoot.

Audio levels should be checked/adjusted before EVERY set-up where anything major has changed (inside/outside, different clothing, room, etc.)

1 PERSON (SINGLE MIC) INTERVIEW/HOST WRAP:

• LAV (mic) should be sent to both channels on the camera

• Both Channels 1 & 2 should be aligned to –12 db using tone sent from the mixer at 0 db (do not use the camera’s internal oscillator to record tone)

• The limiter on the mixer should be turned OFF

• Levels should be consistently recorded above –10 db on the camera’s audio meters and should never reach 0 dB on those meters (most of our mixers have analog VU meters that will not give you an accurate reading for digital peak - please use the camera’s meters whenever possible)

• Audio should ALWAYS be monitored from the CAMERA return (output)… NEVER from the mixer input (except to verify that the signal coming in to the mixer from the mics is not overmodulated prior to recording

2+ PERSON (MULTI-MIC) SETUPS:

2 LAVs: Mics should be separated one on to each channel

3+ LAVs: Mics should be mixed in the most logical way possible (ie. Realtor on Ch.1, husband/wife mixed on Ch. 2 or if you have a soft spoken designer and wife yet a loud husband, you might want to mix the women together on Ch. 1 and send the husband to Ch. 2)

Most audio mixers have 4-5 inputs on them, but some do only have three. When you have more people on camera than you have mics talk to the field director about what tools you have to get the coverage needed and the best way to mix them down to Chs. 1 & 2. If the scene calls for it, shoot the Master then break up the dialogue from shot to shot and use the boom on the closeups for tighter audio.

4+ LAVs: Mics should be mixed in the most logical way.(i.e. Realtor and Husband on Ch.1, Wife and Kids on Ch.2). Again, the logic being mixing people who offset each other like a talkative realtor mixed to Ch.1 along with a semi-mute husband, etc.

6+ LAVs: If the shoot calls for it we may be able to hire a mixer with an 8 Channel mixer/recorder(like the Sound Devices 788T). This gives you 8 discrete tracks of recordable audio going to a separate recording device that will need to be jam synced with the camera. The mixer should still have a Stereo mixdown being sent to camera for the editors(via either wireless hops or hardwired to the camera).

LAVs with Boom: LAVs should be mixed to Ch. 1, Boom to Channel 2

If the LAVs are mixed to 1 channel it is critical that the mics are recorded as close to the same level as possible.

• Both Channels 1 & 2 should be aligned to –12 db using tone sent from the mixer at 0 db (do not use the camera’s internal oscillator to record tone)

• The limiter on the mixer should be turned OFF

• Levels should be consistently recorded above –10 db on the camera’s audio meters and should never reach 0 dB on those meters (most of our mixers have analog VU meters that will not give you an accurate reading for digital peak - please use the camera’s meters whenever possible)

• Audio should ALWAYS be monitored from the CAMERA return (output)… NEVER from the mixer input (except to verify that the signal coming in to the mixer from the mics is not overmodulated prior to recording)

B-ROLL/NAT SOUND & “ROOM TONE”:

• On every take of every shot (A-Roll, B-Roll, Interviews, etc) you must always be recording audio. Even if it’s a pan across a room, or an exterior of a house, we need usable audio… you, the crew, and the participants should minimize background chatter and direction during b-roll shots, construction, projects, room POV’s, exteriors, etc…

• B-Roll audio must be captured using the same microphones as the scene… the on-board camera mic should only be for b-roll, room POV’s, and exteriors not involving the mic’d talent of the show. Example: If a husband and wife are walking their dog in the park and talking they should be LAV’d, a couple walking up to a prospective house with their realtor should be LAV’d… a pan of Baltimore harbor can be captured using the camera’s mic.

• “Room tone” is 15 – 20 seconds of the ambient sound of a room, with no one talking, no music playing, no dogs barking, etc. It’s just the “sound” of the room. Everything in the room affects how room tone sounds. In noisy areas that cannot be avoided (traffic, wind, restaurants, etc) - more room tone should be recorded -- ideally the noisier something is, the more tone we will have to fill in gaps between sound bites.

• You must record room tone with the exact same set-up that you used when you recorded the SOT. That means you, the crew and all the subjects have to be in the same place, wearing their mics, all of the levels should stay the same, lights that were on have to stay on, etc. If an error was made during the actual shoot (a window was left open, something with a fan was left on, etc.) these should not be corrected for the room tone."

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Doubt it's yours, but what a gem:

... • Both Channels 1 & 2 should be aligned to –12 db using tone sent from the mixer at 0 db (do not use the camera’s internal oscillator to record tone)

• The limiter on the mixer should be turned OFF

• Levels should be consistently recorded above –10 db on the camera’s audio meters and should never reach 0 dB on those meters (most of our mixers have analog VU meters that will not give you an accurate reading for digital peak - please use the camera’s meters whenever possible)

Most (all?) modern mixers' 0VU reference is -20dBfs. If following the instructions above, aligning this tone to -12dB at the camera, and levels are monitored at the mixer (which is what the lineup tone is supposed to allow the operator to do), then the camera audio would distort when -10dBfs was achieved at the mixer. Sure, it says to monitor levels on the camera meter instead of the mixer's meter, but when is that practical? Also, if following the guidelines above, there is no need to turn the mixer's output limiters off, because overload at the camera will occur before the limiters activate.

The better way would be to set up the gear in the way it was designed, aligning the 0VU reference tone out of the mixer with -20dBfs on the camera (or other recorder). Adjust levels at the mixer to the desired dynamic range, while avoiding 0dBfs (max).

It's going to take a book.

gt

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Most of the things outlined in the above document (other than the glaring errors Glen pointed out, and a couple of others) are what any professional sound mixer should already know and practice. Most of this document would be unnecessary if they hired experienced pros.

One exception is the part about changing levels during a shot. If that's in there, it should read something like, "It should never be obvious that you've adjusted levels during a shot." In actual practice, gentle, discreet, level riding is part of the job and often makes level changes less obvious, from head turns, bend overs, uneven speaking patterns, and the like. Never do it in a way that hurts post, however -- only do what will help post. If you know something about what the post process will be, you'll be better capable of making these decisions.

The best advice is to become proficient at post prior to mixing on location, then deliver tracks that you'd be delighted to work with if you were doing the final mixing.

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• Both Channels 1 & 2 should be aligned to –12 db

That's generally been the standard for semi-pro cameras for the past ten years. Started with the PD150 and its ilk, which sacrificed some headroom to brag about better s/n. (The PD150 series s/n was so bad that when Sony released the PD170, its AGC was calibrated to -6 dBFS nominal! We won't even talk about its frequency response...)

Recent and pro cameras have been a lot better, at least the ones I've measured. When John Garrett and I tested an Alexa a couple of months ago for CAS Journal, the specs I got were IMHO good enough for theatrical dialog if you're careful. (There are plenty of other reasons not to go single system, even with Alexa. See John's article.)

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  • 2 weeks later...

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snapback.pngJohn Blankenship, on 24 February 2012 - 06:46 PM, said:

The best advice is to become proficient at post prior to mixing on location, then deliver tracks that you'd be delighted to work with if you were doing the final mixing.

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Doubt it's yours, but what a gem:

"PRODUCTION AUDIO GUIDELINES

MIC PLACEMENT:

MICS SHOULD ALWAYS BE POSITIONED FOR THE BEST AUDIO (tightest, most direct sound) centered is usually best unless you know that the subject will be facing a particular direction the ENTIRE scene… if there is any question - keep it centered, high and tight.

We prefer if the mics were hidden. If this is not optimum for the cleanest audio (due to fabric noise, chest hair, etc), then you may expose the mics.

Note: Do not use large, fuzzy windscreens(i.e. Micro Cat, Baby Koala) except in EXTREME conditions. If you absolutely must use these, then make sure they are not prominent in the scene or hidden entirely without compromising your audio.

The mic packs must ALWAYS be hidden.

MICS should not be removed or repositioned unless the subjects clothing has changed… levels should be set BEFORE shooting and should not be adjusted during filming for any reason. If you have to make a slight tweak, do it between takes. If any major adjustment is needed/made, please let the field producer know as they may want to do another take to ensure levels match with the rest of the shoot.

Audio levels should be checked/adjusted before EVERY set-up where anything major has changed (inside/outside, different clothing, room, etc.)

1 PERSON (SINGLE MIC) INTERVIEW/HOST WRAP:

• LAV (mic) should be sent to both channels on the camera

• Both Channels 1 & 2 should be aligned to –12 db using tone sent from the mixer at 0 db (do not use the camera’s internal oscillator to record tone)

• The limiter on the mixer should be turned OFF

• Levels should be consistently recorded above –10 db on the camera’s audio meters and should never reach 0 dB on those meters (most of our mixers have analog VU meters that will not give you an accurate reading for digital peak - please use the camera’s meters whenever possible)

• Audio should ALWAYS be monitored from the CAMERA return (output)… NEVER from the mixer input (except to verify that the signal coming in to the mixer from the mics is not overmodulated prior to recording

2+ PERSON (MULTI-MIC) SETUPS:

2 LAVs: Mics should be separated one on to each channel

3+ LAVs: Mics should be mixed in the most logical way possible (ie. Realtor on Ch.1, husband/wife mixed on Ch. 2 or if you have a soft spoken designer and wife yet a loud husband, you might want to mix the women together on Ch. 1 and send the husband to Ch. 2)

Most audio mixers have 4-5 inputs on them, but some do only have three. When you have more people on camera than you have mics talk to the field director about what tools you have to get the coverage needed and the best way to mix them down to Chs. 1 & 2. If the scene calls for it, shoot the Master then break up the dialogue from shot to shot and use the boom on the closeups for tighter audio.

4+ LAVs: Mics should be mixed in the most logical way.(i.e. Realtor and Husband on Ch.1, Wife and Kids on Ch.2). Again, the logic being mixing people who offset each other like a talkative realtor mixed to Ch.1 along with a semi-mute husband, etc.

6+ LAVs: If the shoot calls for it we may be able to hire a mixer with an 8 Channel mixer/recorder(like the Sound Devices 788T). This gives you 8 discrete tracks of recordable audio going to a separate recording device that will need to be jam synced with the camera. The mixer should still have a Stereo mixdown being sent to camera for the editors(via either wireless hops or hardwired to the camera).

LAVs with Boom: LAVs should be mixed to Ch. 1, Boom to Channel 2

If the LAVs are mixed to 1 channel it is critical that the mics are recorded as close to the same level as possible.

• Both Channels 1 & 2 should be aligned to –12 db using tone sent from the mixer at 0 db (do not use the camera’s internal oscillator to record tone)

• The limiter on the mixer should be turned OFF

• Levels should be consistently recorded above –10 db on the camera’s audio meters and should never reach 0 dB on those meters (most of our mixers have analog VU meters that will not give you an accurate reading for digital peak - please use the camera’s meters whenever possible)

• Audio should ALWAYS be monitored from the CAMERA return (output)… NEVER from the mixer input (except to verify that the signal coming in to the mixer from the mics is not overmodulated prior to recording)

B-ROLL/NAT SOUND & “ROOM TONE”:

• On every take of every shot (A-Roll, B-Roll, Interviews, etc) you must always be recording audio. Even if it’s a pan across a room, or an exterior of a house, we need usable audio… you, the crew, and the participants should minimize background chatter and direction during b-roll shots, construction, projects, room POV’s, exteriors, etc…

• B-Roll audio must be captured using the same microphones as the scene… the on-board camera mic should only be for b-roll, room POV’s, and exteriors not involving the mic’d talent of the show. Example: If a husband and wife are walking their dog in the park and talking they should be LAV’d, a couple walking up to a prospective house with their realtor should be LAV’d… a pan of Baltimore harbor can be captured using the camera’s mic.

• “Room tone” is 15 – 20 seconds of the ambient sound of a room, with no one talking, no music playing, no dogs barking, etc. It’s just the “sound” of the room. Everything in the room affects how room tone sounds. In noisy areas that cannot be avoided (traffic, wind, restaurants, etc) - more room tone should be recorded -- ideally the noisier something is, the more tone we will have to fill in gaps between sound bites.

• You must record room tone with the exact same set-up that you used when you recorded the SOT. That means you, the crew and all the subjects have to be in the same place, wearing their mics, all of the levels should stay the same, lights that were on have to stay on, etc. If an error was made during the actual shoot (a window was left open, something with a fan was left on, etc.) these should not be corrected for the room tone."

No, this isn't mine--I'm not interested in telling soundies how to do sound--they are on their own about that. I mean info about the nitty gritty of file naming, TC, prepping for transcription etc etc that are peculiar to that prod.co's workflow.

phil p

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Doubt it's yours, but what a gem:

"PRODUCTION AUDIO GUIDELINES...

Man, if somebody handed me something this insulting , I'd say, "give me five minutes and I'll give you a list of Do's and Don'ts for your script." angry-smiley.gif

I don't mind a delivery document that says, "hey, we want X on channel 1, Y on channel 2, label the files this way, and keep your levels at Z," that's fine. But don't tell me my job.

This would be as obnoxious as handing a DP a spec sheet that says, "be sure all the interview subjects have the right head room. Make sure you focus the lens before rolling. Check the exposure to make sure it's not too bright, and not too dark. Light the scene in a way that flatters the subject and doesn't make them look bad." Etc.

I would have no problem if this were a "Filmmaking 101" document given to neophyte students.

About the only similar thing like this I've ever had was the opposite problem, when I worked on a documentary about a year ago, and after a few takes, I took the (very young) director aside and said, "hey, I don't mean to overstep my bounds, but for sound editing purposes, you may want to have the interview subject re-state the question as part of their answer. As in, 'I first met Mr. X back in Cleveland, when we had a police problem...' or whatever the subject is." He seemed taken aback that I was interfering with strict documentary rules (no putting words in the interviewee's mouth), and said, "no, no -- we don't work that way." I said, no problem, you can probably still make it work.

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Light the scene in a way that flatters the subject and doesn't make them look bad." Etc.

Now, I have been on a documentary where the director took the cameraman aside and quietly told him, "This guy's an SOB. Light him from the floor!"

Can't recall for sure if the cameraman obliged. I think he just lit a little flat to hedge his bets.

David

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  • 2 weeks later...

The best advice is to become proficient at post prior to mixing on location, then deliver tracks that you'd be delighted to work with if you were doing the final mixing.

yup. post guys should know about production duties. production guys should know about post duties. helps even more if you have experience in both, even if you only plan on focusing on one and not the other.

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About the only similar thing like this I've ever had was the opposite problem, when I worked on a documentary about a year ago, and after a few takes, I took the (very young) director aside and said, "hey, I don't mean to overstep my bounds, but for sound editing purposes, you may want to have the interview subject re-state the question as part of their answer. As in, 'I first met Mr. X back in Cleveland, when we had a police problem...' or whatever the subject is." He seemed taken aback that I was interfering with strict documentary rules (no putting words in the interviewee's mouth), and said, "no, no -- we don't work that way." I said, no problem, you can probably still make it work.

i've had similiar experiences...

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And this was an entertainment documentary, not something about AIDS or child abuse or something.

I'm reminded by something John Coffey said in his famous "The Letter" document years back: reminding the director that, chances are, there are members of the crew who have written and directed and done other things, and might actually know your job almost as well as you do. I think some neophytes are a little shaken to realize that.

It's a good question as to whether to keep your mouth shut or bring it up. I gots no answer for that.

Knowing the camera side of things is very important in the post business, especially for colorists. It helps to be able to talk lenses, filters, key-to-fill ratios, exposure, and all that stuff with the DP. I think I've learned as much or more from the DPs over the years as they have from me. Far too many of them are intimidated by the dancing lights and 167 knobs in a color-correction room; I always tell them, "nothing matters except what's up there" (on the screen). The rest of it is like the speedometer in a car: the meters tell you when you're over the limit.

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This would be as obnoxious as handing a DP a spec sheet that says, "be sure all the interview subjects have the right head room. Make sure you focus the lens before rolling. Check the exposure to make sure it's not too bright, and not too dark. Light the scene in a way that flatters the subject and doesn't make them look bad." Etc. I would have no problem if this were a "Filmmaking 101" document given to neophyte students. About the only similar thing like this I've ever had was the opposite problem, when I worked on a documentary about a year ago, and after a few takes, I took the (very young) director aside and said, "hey, I don't mean to overstep my bounds, but for sound editing purposes, you may want to have the interview subject re-state the question as part of their answer. As in, 'I first met Mr. X back in Cleveland, when we had a police problem...' or whatever the subject is." He seemed taken aback that I was interfering with strict documentary rules (no putting words in the interviewee's mouth), and said, "no, no -- we don't work that way." I said, no problem, you can probably still make it work.

Hey for what its worth I have been handed a document like this when I was the dp on some corporate stuff. I have also been ac on jobs where the dp received one as well. Usually has more to do with somebody having been burned bad in the past, we have all heard the horror stories at some point.

The problem is that the client who does not know anything about the procedures or demands in the field usually ends up running to somebody like your neophyte producer or this girl they know who used to be a reporter or some other nonsense for help composing a Quality control document. Which usually turns into a nightmare/hoot or a read.

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I saw the other thread, yes, but I think this is the more appropriate place to put this.

There are few different ways you need to mix audio for post depending on the medium and destination you will be outputting to.

For TV, you will be provided a spec sheet of what you output peaks should be maxed at. For commercials, usually it is based on a maximum LEQ, but I think that has changed of recently (haven't done post on a commercial in while.)

film and theater release is a whole different animal. There is no "standard" peak level.

When doing post audio for theater release the most important thing is to have a properly calibrated system. the proper calibration is...

First start with a pink noise reference of -20dbfs

each line out should be set to 1.23V(+4db) with this reference.

once each output is double checked for V, each speaker should be set to read 85dB on a spl meter placed in your mixing sweet spot. each speaker and output should be calibrated individually.

once the room is calibrated, mix with your ears, not the meters. If you think the dialog is too loud, turn it down. If you think it is to low, turn it up. Theaters are set up to this same reference (usually) so the way it sounds on the mixing stage, will be the way it sounds in theaters. Again, don't mix to the meters for theater.

this is perfect if you're talking stereo.

in a 5.1 environment i believe the rear speakers are to be set at 82db. the sub should be hoovering between 90 and 91db.

can anyone verify?

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this is perfect if you're talking stereo.

in a 5.1 environment i believe the rear speakers are to be set at 82db. the sub should be hoovering between 90 and 91db.

can anyone verify?

It really depends on the room. you are not incorrect, but there are a lot of different guidelines. for example, when mixing for TV in 5.1 the reference levels are around 80db (give or take a db or 2). Room dimensions also play a part. I was just trying to keep it as simple as possible.

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It really depends on the room. you are not incorrect, but there are a lot of different guidelines. for example, when mixing for TV in 5.1 the reference levels are around 80db (give or take a db or 2). Room dimensions also play a part. I was just trying to keep it as simple as possible.

didn't know that about TV. why does the room size matter? besides acoustics. shouldn't a "good" mix translate to any listening environment well? and besides "straight to dvd movies" aren't most films mixed in a theater? would be weird to mix it in a room and expect it to play back well in a theater...

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would be weird to mix it in a room and expect it to play back well in a theater...

That's why it changes depending on the room. The majority of people that visit this site interested in this subject will not be mixing in a theater, but following these guidelines will make the mix translate to the theater well.

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That's why it changes depending on the room. The majority of people that visit this site interested in this subject will not be mixing in a theater, but following these guidelines will make the mix translate to the theater well.

gotcha. you're probably right. not everyone can afford a 2 million dollar dolby mix theater. even a small one. :D

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Good news: according to this week's TV Technology, people are starting to make noises about setting a dBFS=SPL standard for live / live-to-tape audio rooms. They're somehow catching on to the idea that "mixers set levels with their ears, and then occasionally check the meters".

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