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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.

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Mix levels on a dub stage do have very specific levels for Dolby and THX. Mixing by ear is only part of it but final delivery specs depend on the final delivery medium. Same goes for broadcast. Each TV outlet has their own specs and a proper mix level must be made accordingly. It is not a willy-nilly free for all like you make it sound.

www.matthewfreed.com

Production Sound Mixing for TV, Films, and Commercials

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Mix levels on a dub stage do have very specific levels for Dolby and THX. Mixing by ear is only part of it but final delivery specs depend on the final delivery medium. Same goes for broadcast. Each TV outlet has their own specs and a proper mix level must be made accordingly. It is not a willy-nilly free for all like you make it sound.

www.matthewfreed.com

Production Sound Mixing for TV, Films, and Commercials

Dolby is a encoding standard and THX is a listening environment standard. I don't believe any of them have anything to do specifically with what level a mix should be at.

Except for calibration levels of course....

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Stupid question for us in production...

There was a lively discussion about mix levels on set. I am in the "mix it hot - it's digital. Avoid compression and don't clip (duh)."

If post is getting varying levels from different production mixers, can't post just turn the production track down (as long as there's no clipping) or turn it up (as long as there isn't a high noise floor), in order to achieve the levels they desire? If I deliver sound peaking at -3dBFS, but deliver specs are -8dBFS peaks, can't post mix in my mix track at a lower level?

Question seems stupid, sorry, but wondering if there is some voodoo, or is it a simple fader move.

Robert

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Stupid question for us in production...

There was a lively discussion about mix levels on set. I am in the "mix it hot - it's digital. Avoid compression and don't clip (duh)."

If post is getting varying levels from different production mixers, can't post just turn the production track down (as long as there's no clipping) or turn it up (as long as there isn't a high noise floor), in order to achieve the levels they desire? If I deliver sound peaking at -3dBFS, but deliver specs are -8dBFS peaks, can't post mix in my mix track at a lower level?

Question seems stupid, sorry, but wondering if there is some voodoo, or is it a simple fader move.

Robert

Yes, Robert. That's called mixing ;)

It used to be much more important for the production mixer to keep the levels very consistent becuase there was no way for the editor to easily adjust it when cutting different angles together. Now that we are using Avids and ProTools, it is very easy for the editors to adjust tracks that are out of whack when cut together.

I mix by ear, no matter what the medium. I may change my monitor setup, but I usually use the behind the screen monitors (big speakers) and adjust the level of those when I mix for DVD or TV. I check my mixes on nearfield monitors. But those setups, once calibrated, are never changed.

Theatrical features are done at 85db SPL (C weighted). When I mix for TV I turn the monitors down to 80 db to mix and then check the mix on nearfelds. This forces a natual compression of dynamic range for TV or home setups. I know from experience how my room will translate in each situation, so once the monitors are set I really only use the meters to check for clipping and that things are properly coming out where they belong. All other decisions are made by ear.

As far as what levels you should shoot for on the set? If you want to use compression keep it very light. I would say leave all of your EQ out and only high or low pass if there is a really good reason to do it. That kind of thing is better left to post.

Hope this helps...

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If post is getting varying levels from different production mixers, can't post just turn the production track down (as long as there's no clipping) or turn it up (as long as there isn't a high noise floor), in order to achieve the levels they desire? If I deliver sound peaking at -3dBFS, but deliver specs are -8dBFS peaks, can't post mix in my mix track at a lower level?

Yes. But the real problem is not with the re-recording mixer; it's with the editor, producers, director, and execs who watch the dailies. If the levels bounce around wildly -- and not all editors are prepared to go in and tweak lots of levels if the sound comes from different mixers -- people tend to complain.

I've never gotten a complaint about levels being too hot, but a few times I have gotten complaints about levels being a little too low. Not horribly low, just lower than they're used to. I think if the mix track is limited and peaks a hair above -10dBf, they're not going to complain. The iso tracks can easily be 5dB lower (or more), which is well within correctable range. When I was involved in dailies years ago, I would get nervous if I got in a production track that was clipping every :30 seconds; I would usually drop the level slightly and slip in a limiter on the board during dailies transfers, and quietly send an email or make a phone call to the sound mixer. This happened very, very rarely.

Sound levels for final mixes are a huge issue these days, especially with the Discovery Channel. The ITU Loudness Standard is quickly becoming the rule for TV shows and commercials, in establishing average overall levels, peak levels, and average dialog levels. At least now, the QC people can literally run the whole show through a box -- without listening to it! -- and give you a print-out that tells you where the show didn't meet the spec. It doesn't guarantee dialog intelligibility, depending on how busy the mix is, but at least it's a step in the right direction.

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Yeah, stations, networks, and studios are all rewriting their specs, generally along the ITU guidelines. That takes care of the programs; the real problem are the commercials and promos, where the levels go all over the place. What makes me nervous is that some stations are just going to slap a black box in the program path, letting the box "legalize" all the levels. I'm concerned that this is going to undo a lot of mix decisions and make everything sort of "homogenized," which will have a drastic effect on creative decisions in the original mix.

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I'm not too concerned about the "black box"... it's really no different than the Optimods and other transmitter processors TV stations have been using for years, to force varying signals through an analog broadcast chain.

What it _will_ do, sort of, is keep the volume relatively stable when you switch from one station to another... once it's fully implemented, which will take a long time considering how many tv sets can't read dialnorm yet, and how many exceptions there are for small stations or cable systems that don't want to provide a separate box for every channel they carry.

--

I predict that, even after CALM is fully implemented, agencies will be after us to invent some way to make their commercials louder.

And we will.

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I predict that, even after CALM is fully implemented, agencies will be after us to invent some way to make their commercials louder.

Note that all of this started happening after many TV stations and networks cut their engineering staff. I've maintained for years that loudness variations between programs and commercials is a human problem, not a technical problem. If you have a human being checking the commercials before they're aired, they can just adjust the volume to compensate.

In the days when I worked on broadcast shows and we controlled both picture and sound during mastering, I would regularly check the satellite feed later on and listen to how the show compared to the commercials. Usually after a period of weeks, I'd bump the program level up so that there was no longer much of a difference between the two. That was easier than telling the network to drop the commercial levels. I have definitely seen commercials so loud, the VU meter would just pop up and hover almost at "0" for the entire spot, barely moving. Zero dynamic range.

Sadly, I think this problem has gotten worse after the switch to HD. I think nobody's watching (or listening) back at the ranch.

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Just chiming in to agree with some of the previous responses. As an editor and mixer it is always easier to deal with loud material than under-recorded material. This may change somewhat with clip-based gain in Pt 10, but in general it is easier to turn down by a few dB than to try and dig stuff out of the dirt. it is nice to get a warning when stuff is really loud. Either in the voice slate or the log, indicate when something has gunshots or unexpected yelling.

Thanks,

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My vote is for....getting the level in the "zone" in the field! I have always had clip gain in my system, so the first 12 db either way of adjustment is no issue, but it's easier for editors having to do demo mixes to not have to do a lot of gaining around for each clip. Remember that their mix has to be approved as part of the cut before we audio posties get the show. Having things too low results in editors "doubling up" tracks--ie copies of the same clip on more than one track--to get the level up, so WAY low is more of a problem for them than way hot. If anything, I seem to see more very hot audio (like clipped) coming to me than under-recorded stuff these days.

To Tom F--big props to you for all you've done, but you will start a bar fight around here if you tell production soundies to not use their EQ, esp on their mix!

phil p

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Welcome to the forum Tom! It's great to have an experienced post person here.

Theatrical features are done at 85db SPL (C weighted). When I mix for TV I turn the monitors down to 80 db to mix and then check the mix on nearfelds. This forces a natual compression of dynamic range for TV or home setups. I know from experience how my room will translate in each situation, so once the monitors are set I really only use the meters to check for clipping and that things are properly coming out where they belong. All other decisions are made by ear.

Excellent advise in these posts! It's so hard to explain setup/calibration and many people have different ideas about how to go about it. I think it helps coming from someone who knows.

If post is getting varying levels from different production mixers, can't post just turn the production track down (as long as there's no clipping) or turn it up (as long as there isn't a high noise floor), in order to achieve the levels they desire? If I deliver sound peaking at -3dBFS, but deliver specs are -8dBFS peaks, can't post mix in my mix track at a lower level?

It's definitely easier to turn it down than up. Pro Tools only has 12db of boost on a channel fader and some more with the trim parameter. After that you have to use the Gain audiosuite plugin to boost. You manually select a region, set the amount of gain, and apply it. This creates a new file on the storage medium. If the region is already edited in place you have to pull it down to a different channel, pull out the handles at each end and do the gain process. This is time consuming. If the region was part of a polyphonic package of files the newly created file will have a slightly different name. Etc, etc, etc…

Mark O.

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My vote is for....getting the level in the "zone" in the field! I have always had clip gain in my system, so the first 12 db either way of adjustment is no issue, but it's easier for editors having to do demo mixes to not have to do a lot of gaining around for each clip. Remember that their mix has to be approved as part of the cut before we audio posties get the show. Having things too low results in editors "doubling up" tracks--ie copies of the same clip on more than one track--to get the level up, so WAY low is more of a problem for them than way hot. If anything, I seem to see more very hot audio (like clipped) coming to me than under-recorded stuff these days.

Perhaps I was not clear. I wasn't saying that no effort should be made to keep things consistent. Obviously it is still important for all of the reasons stated above. That said, in the old analogue days, adjusting the production track levels for the cut, which in those days was most likely a single strand mag stripe of the production dailies cut together, was a pretty huge deal. It could not be done on a moviola by an assistant or an apprentice. I worked for 12 years in a transfer room before I began doing mixes, so believe me, I know. I was the guy who did the adjusting for them. In fact, I would consider that part of my job as the beginning of the training I got as a re-recording mixer. So yes, it is important to maintain consistent levels, but maybe not as crucial as it used to be.

To Tom F--big props to you for all you've done, but you will start a bar fight around here if you tell production soundies to not use their EQ, esp on their mix!

I kinda knew that, but I had to say it anyway. What I don't know won't hurt me, if you get my drift...however when it comes to editors using signal processing? ... Now that's a whole other issue ;)

And regarding recording levels, hotter is better, until it starts clipping...that said, overly limited tracks kinda suck too, so that only goes so far.

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Hi to all.

Tom a question about mixing for you if you have a mo..

I have been location mixing for about five years having boom opped for the guts of 14 years before. More and more I see a disconnect between a directors/productions understanding of what it takes (technically) to deliver a quality product... the fix it in post mantra is being taken to new extremes. Where as a proper tech rehearsal would eliminate most of the issues we get presented with.

More and more (on lower budget films) I find we get one take on one slate with no rehearsal, or a rehearsal that bears no resemblance to the actual take, making it near impossible to do a good mono mix, salvaged only by the iso's.

So I guess my question is.... when delivering a mono mix down and what ever number of iso's needed would you....

(A) prefer to hear an attempt at a mix given the high likelyhood of ad-libs being missed or ...

( 8) fade everything up so that you have all the dialogue (scripted and unscripted) on the mono mix down so that dailies are more digestable and the iso's get remixed later

What do you think ??

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Hi to all.

Tom a question about mixing for you if you have a mo..

I have been location mixing for about five years having boom opped for the guts of 14 years before. More and more I see a disconnect between a directors/productions understanding of what it takes (technically) to deliver a quality product... the fix it in post mantra is being taken to new extremes. Where as a proper tech rehearsal would eliminate most of the issues we get presented with.

More and more (on lower budget films) I find we get one take on one slate with no rehearsal, or a rehearsal that bears no resemblance to the actual take, making it near impossible to do a good mono mix, salvaged only by the iso's.

So I guess my question is.... when delivering a mono mix down and what ever number of iso's needed would you....

(A) prefer to hear an attempt at a mix given the high likelyhood of ad-libs being missed or ...

( 8) fade everything up so that you have all the dialogue (scripted and unscripted) on the mono mix down so that dailies are more digestable and the iso's get remixed later

What do you think ??

No one will tolerate any lines not getting recorded, so I am assuming that you mean that the iso's will be recorded regardless of what finds it's way into the mix you do. I think your question is best aimed at the the film editors. They will be doing all manner of mad and creative things with the tracks when in putting the cut together. They cheat lines from different takes, they create new lines out of whole cloth, they take lines from other scenes and put them in if need be, so there is no clear answer to that, but good communication, again, is key. Talk to the picture editor and ask them what they would like. Are the options limited to a unity mixdown which is overly noisy and may have spurious and unwanted sounds? Or would they like an attempt at a mix that they can use to cut with but which may miss some unrehearsed ad lib? I don't really know, but if I was the editor I'd probably want a mix. If something gets missed it can be found in the iso and added back in the Avid. By the time the tracks get to me at the mix stage, the dialogue editors have gone through them and selected the best options for each angle so I hardly ever see the mixdown track unless it's is provided as the best option for the shot.

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" a proper tech rehearsal "

actually, that would be the "blocking rehearsal", done before the camera begins its setyp (placement and lighting). after the blocking rehearsal, when marks are set down, the standin's step in, the actors go to hair-,/i-wardrobe, and the crew sets up the shot. There is also supposed to be one (at least) rehearsal after the set-up; is finished and the "first team" returns to the set, to alow final tweaking of the set-up.

Ah, yes, I do miss the old way! ::)

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  • 1 month later...

Stupid question for us in production...

There was a lively discussion about mix levels on set. I am in the "mix it hot - it's digital. Avoid compression and don't clip (duh)."

If post is getting varying levels from different production mixers, can't post just turn the production track down (as long as there's no clipping) or turn it up (as long as there isn't a high noise floor), in order to achieve the levels they desire? If I deliver sound peaking at -3dBFS, but deliver specs are -8dBFS peaks, can't post mix in my mix track at a lower level?

Question seems stupid, sorry, but wondering if there is some voodoo, or is it a simple fader move.

Robert

I've often wondered about this as well. If the signal is coming close to full scale, though, isn't there a possible problem with any further processing that post might want to do. Like Eqing or compression. To hot of a level doesn't really leave you much to work with. Or is just a matter of using a plugin or whatever feature in the Daw or edit suite to bring the level down to a lower level?

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as long as you don't clip, post can get done whatever they need to get done. If they need a little head room they can adjust the input level of the plug-in or hardware being used. It just adds that extra step to the process.(which isn't really much of a step)

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as long as you don't clip, post can get done whatever they need to get done. If they need a little head room they can adjust the input level of the plug-in or hardware being used. It just adds that extra step to the process.

True, but: they'll complain about it. This is particularly a problem when they're getting tracks from different people every week, or every month. Anything you do gets compared to the last guy's sound. If your levels are quite a bit lower, or slightly lower, they may well find this annoying. If the levels are in the ballpark, then they can deal with it.

They can always drop a Trim plug-in into the channel strip on Pro Tools to give you an extra +6dB, but it's an annoyance, especially if you're already 2/3 through a mix and just got some new tracks in.

Edited by Marc Wielage
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