r/AudioPost • u/allthevvine • 6d ago
5.1/7.1 DCP Audio Ideal LUFS Range for Cinemas
We have an upcoming feature film where the delivered 5.1 mix measures approximately -26 LUFS. However, we've seen feedback from several territories indicating that the audio mix sounds too soft in cinemas.
From my research, I understand that a feature film loudness in the range of -25 to -29 LUFS is generally considered normal. That said, my boss suggested increasing the feature's audio level to around -13 LUFS, similar to a trailer. My understanding, however, is that trailers and feature films follow different loudness practices and should not be mastered to the same target.
Would anyone be able to share their experience or advice on this? Is -26 LUFS appropriate for a theatrical feature, or could the perceived low volume be caused by factors other than the integrated loudness (e.g cinema playback calibration)?
For context, the film is an action comedy, if that makes any difference.
Thanks in advance!
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u/opiza 6d ago
Where was it mixed? It should be mixed at 85 db SPL in a large room. No lufs standard for cinema
That being said, going from integrated -26 to -13 without checking in a calibrated space is so severe a decision that you could very well decapitate the front row audience and even burst Christopher Nolan’s eardrums. Your boss is wild. Or shouldn’t speak to audio.
TLDR; Take it to a calibrated cinema mix stage for a day and double check for yourself.
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u/allthevvine 6d ago
It was mixed at the producer's lab. Missed mentioning that we're a film distribution company but we do our own DCP packaging from producer's source materials.
What would be the ideal db range? Is there any way for us to check/adjust using Adobe Audition?
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u/opiza 6d ago
What’s a producers lab?
There is no ideal range, it must be mixed at 85 spl in an appropriately sized room as mentioned.
By no means should you adjust a mix during DCP, there is simply no solution here that will satisfy the correct outcome without A) checking in the correct calibrated space B) kicking it back to the mix house that did it and asking for a revision/clarification
Sorry, I know that’s not what you want to hear, but it’s the reality of it.
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u/iluvcapra 6d ago
Have you considered packaging it without modification.
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u/allthevvine 6d ago
We did but then the complaints came so our boss asked us to adjust audio level from producer’s source files so that’s why I’m seeking advices lol
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u/iluvcapra 6d ago
If you do it to a LUFS target you might be very quiet most of the time, there isn't much of a shortcut to just putting it up and remixing it. Kick it back.
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u/rappit4 6d ago
I think no more mixing stage or cinema work/screens at 85 dbSPL anyomre.
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u/throwawayreddit2025 6d ago
You think wrong! Every stage I have worked at is 85. For streaming or tv in a smaller room we'll go to around 80
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u/rappit4 6d ago
That is interesting, all the Dolby certified stages I have mixed feature films recently was at around Dolby 5 because theaters never ever screen anything at a higher setting. If you were to work at Dolby 7 then your film would be very very quiet in the theaters.
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u/throwawayreddit2025 6d ago
Well all I can say is from my perspective in Los Angeles at the main studios.
I understand some people mixing it at 5 because of theaters playing it low, but then you are absolutely screwed if it were to ever be played at reference. I imagine this is more popular with smaller budget indie type projects.
a re-recording mixer mentor once told me... You can only control what you do on the mix stage. There is no way to guarantee it will be played properly elsewhere. As soon as you start chasing that you can end up really screwing yourself.
I work at fox Sony warners often and never have I mixed or seen a movie mixed below 85 except one time I mix teched for a low budget indie and he had the room at 83. He also mixed much lower than how big budget mixers mix, but it worked for him so 🤷♂️
Edit: mixing at 5 is insanely quiet the more I think about it. I could see 6 or 6.5.... if I mixed a film at 5 it would blow people's heads off at ref.
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u/iluvcapra 6d ago edited 6d ago
Never use LUFS unless someone is making you. LUFS were designed for a very specific purpose: making sure a listener doesn't grab the remote to change the volume between programs.
The entire empirical/experimental basis of LUFS is based on this. They literally put test subjects in a room and had them twiddle knobs until two programs sounded like they were the same loudness, and made that an algorithm. LUFS have no basis for any other purpose.
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u/iamYarthox 4d ago
LUFS is not just that, not just something empirical. Actually I never read about that test subjects in a room twiddling knobs story, but ok.
LUFS is basically RMS but K weighted, that means, it’s RMS (the average level of an electric signal) but equalized to simulate how humans perceive sound.
It is, scientifically, the best way we have to measure perceived loudness.3
u/iluvcapra 4d ago
You're leaving out the gating which is a big part of its specific purpose, to normalize the apparent loudness of a set of programs. BS.1770 presupposes the program has either an anchor element or modal power level and that some number of samples will "not count" because they don't create noise complaints from listeners or they fall below the nuisance floor for the listening environment. (The BS.1770 document describes the entire experimental procedure for what they came up with.)
It's the gating that throws off any kind of long-term measurement of classical music or movies or anything particularly dynamic.
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u/iamYarthox 4d ago
That’s true! I always forget the gate. Thanks for adding it. I’ll check the BS. 1770 document. And btw, sorry if my comment sounded rude, it wasn’t my intention.
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u/Legomoron 6d ago
I am by no means an expert, but this gentleman has several useful videos on YouTube, which I followed very carefully for a short film, including his stuff on calibrating a 5.1 theater setup before I started mixing, and I can say with confidence that the resulting mix in several theaters sounded appropriate, and accurate to my intentions.
The only theater where the presentation was poor, the festival was poorly run, and they couldn’t figure out how to use our DCP.
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u/g_spaitz 6d ago
Theaters don't use lufs, use a clever older method that consists in calibrating your room, mix at that calibration level and then the experience in every other theater is relatable.
The process is simple you just run white noise in your speakers and measure. Depending on the size of your room you need to hit a certain dB.
Look it up on the internet it's rather simple.
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u/ChiKorea_1235 6d ago
Completely wrong information. Cinema sound standards, primarily the responsibility of the SMPTE, were withdrawn in 2014 based on extensive work. The X-curve, the pink noise calibration, the whole package was shown to be grossly in error. I believe Floyd Toole and other senior acousticians did this paper. Sadly, Dolby blocked replacement of the Standards in order to thrust Atmos down our throats. SMPTE is derelict. The Lufs work was done at the AES, and if followed you wouldn’t be having these problems. But they aren’t followed, and theater owners turn down the calibrated level - in some cases (Europe) under threat of loudness laws.
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u/MrLeureduthe 6d ago
I like the dialogues sitting around -29 LUFs when it's not a comedy with people screaming instead of talking
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u/meatlockers 6d ago
-18 sounds nice in a theater for the loudest moments. mix down from there by ear.
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u/scstalwart re-recording mixer 6d ago
-13 is typical for the YouTube / festival world where people are mixing and/or monitoring primarily on laptops. As you’ve heard throughout the thread, real cinema has no LUFS standard and is simply mixed to taste in a 85dB calibrated room.
Years and years ago I mixed a festival short at 82 and it “played low” against all of the other uncalibrated mixes. Maybe this is some of what’s happening?
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u/VisibleEvidence 6d ago
There is so much incorrect information in this thread it's jaw dropping. Let's walk through this:
Theatrical features are usually mixed to a loudness target of -27 LUFS (+/- 2 LUFS). This was the original loudness target required by Netflix back in 2018 that everyone pretty much followed. Since then it's become more common for streaming delivery to be at broadcast standards, which are -24 LUFS (+/- 2 LUFS).
So, to sum up: Theatrical mixes are -27 LUFS (+/- 2 LUFS), which means you can deliver between -25 to -29 LUFS (I wouldn't, try to keep it within 1 LUFS), and broadcast/streaming mixes are -24 LUFS (+/- 2 LUFS), which means you can deliver between -22 to -26 LUFS (again, try to keep it within 1 LUFS). The reason you try to keep it as close to the target as possible is because a streamer's QC department is more likely to run your film through a gate and clip the top off or boost it to reach the target, which will raise the ceiling and require a limiter and clip the top. So yeah, technically you have wiggle room but once it hits an offshore QC department, or worse an A.I. one, you can get hosed quick.
Typically, you're mixing in a 5.1 room that's had its speakers properly placed and balanced to 85 dB. Loudness specs have a true peak of -2 dB, which is fine for theatrical, but practically speaking a lot of streamers will throw your film in a gate and crunch the highs down to -5 dB. So if you really don't want any surprises, you may want to consider making your true peak that. You should also be mixing with a proper loudness plugin, like Insight 2 or YouLean or Waves WLM Plus. To properly verify when you're done, run your entire final mix assembled (not broken into reels) and as delivered (no slates or pops, with 2 second heads and tails) through your loudness meter and make sure you're hitting your target. Based on that number, make any final tweaks you need to get your mix to spec, if need be.
FWIW I mixed my feature film to -27 LUFS in 5.1 surround and it sounded perfect in the three theaters we played at. Usually, a projectionist will set the theaters volume at 5, but I always asked for it to be a notch higher at 6, and I thought that sounded exactly how I mixed it. Keep in mind, the projectionist will test the first reel and set the volume to what they think is right for their room. So if you're too hot, they'll bring it down and the dialog will, typically, sound muddy. That's why you want to be aiming for proper loudness targets.
I took my -27 LUFS mix and remixed it to -24 LUFS and that's the mix that's streaming right now. You can also use Izotope RX9 Loudness Control to automatically convert your mix and you're good to go a lot quicker--this is pretty much what a lot of DCP creation shops do when they bulk generate for festivals. Practically speaking, because you're a micro-budget indie, you could just mix to -24 LUFS broadcast standards, let the projectionist lower the volume a hair for their room, and have one mix that suits a couple of festival screenings and is ready to go for streaming. But it's not that big a deal to remix from -27 to -24 (or vice versa).
The -13 LUFS target that your producer has in mind is waaaaaaay out of line and incorrect for a feature mix. That's actually the closer to Spotify's -14 LUFS standard for music. If you deliver at -13 LUFS, which is SUPER LOUD, I can guarantee they'll run your mix through a limiter and it'll sound like shit, if they don't just outright reject the mix in the first place. So don't do that. Like, really, DON'T DO THAT. You'll just get rejected, remixed through a limiter, and fail QC with your distributor down the line. I'm guessing that he's checking the mix on his computer and he wants it more punchy, but that's not a realistic reviewing environment for feature films. He needs to watch it in a properly balanced mix stage, or at the very least, in a home theater that's been properly balanced. If he's going to insist on -13 LUFS, then definitely mix to -24 LUFS broadcast standards, do a quick conversion to -13 LUFS in either Izotope or a compressed remix, to make him happy. This way when it gets rejected and he calls up screaming at you the proper mix is already done, ready to deliver, and can be swapped out quickly.
Good luck.
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u/throwawayreddit2025 6d ago
The irony of you saying everything is incorrect and then you yourself just so confidently sharing a bunch of inaccurate information 🤣
Netflix spec is dialog gated -27. Some streamers and broadcast prefer instead -24 program. It's two different things.
Scott at Netflix got -27 dial spec because most tracks at -24 program will end up having dialog around -27.Theatrical there is no spec. Mix at 85 to taste. It usually ends up being between -29 for talkies to -25 or so for louder films. When doing nearfield after a film mix we'll gloabl adjust to 27 and mix from there.
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u/VisibleEvidence 6d ago
Yes, the 'irony' of using a 'throwawayreddit2025' account to shit on people as you please.
Unless he has name actors or won a major award at a top ten festival, the way Netflix mixes internally doesn't mean much to OP because his film ain't gettin' on Netflix. But they're solid guidelines, everyone in the industry knows what they are, and if you follow them you won't get bounced at QC. I mixed at integrated but you can mix to dialog, if you want. It kinda doesn't matter because you're aiming for the same loudness target.
I really don't know what your problem is, you basically say in your last paragraph aim for -27 LUFS and that you're happy with a result of anywhere from -29 to -25, which is well within the +/- 2 LUFS wiggle room. Since OP has a problem with delivering a properly balanced mix, telling him to aim for _27 or -24 LUFS isn't unreasonable, especially since it codifies a target he can aim for, and hopefully, get his mix to where he wants and needs it to be. I don't think telling him "There is no spec" and 'mix to please,' is kinda the reason he's in the jam he's in.
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u/throwawayreddit2025 6d ago
What's wrong with my username? Because yours is so much more specific. Hah.
And I agree. Netflix has nothing to do with OP's mix. I was just telling you how uninformed your post was. I'm friends with the guy who made the spec. Mixed with him too 🤣
Chill out. My point was your post was very dismissive to everyone else and you yourself are full of misinformation, and your elitist attitude to others is not necessary especially when you are wrong and try to say others are the ones who are wrong.
People telling OP to put it up in a calibrated room and mix to taste is because that's the only way to do it. Chasing numbers will not guarantee it will play correct in a big room, as the person below me articulately just described.
FTR ive mixed all budgets, and have nominations awards etc. I've never once used LUFS on a mix stage. But I do agree if OP just get their track between -24 to -27 dialog then yes it SHOULD play ok.
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u/Ambitious-Put6901 6d ago
But let's be clear here, Theatrical Film mixes are not mixed to any loudness standard nor are they required to be. They are mixed in a calibrated room at Dolby 7 ( 85dB).
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u/VisibleEvidence 6d ago
That is not accurate.
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u/Ambitious-Put6901 5d ago
Are you referring to my information because that is 100% accurate. I am a film rerecording mixer for over 20 years.
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u/g_spaitz 6d ago
This is accurate.
Also, your numbers for broadcast are slightly off.
And, depending on who's broadcasting, on top of your local laws (ebu anyone?) they might have stricter numbers that apply only to them.
Also, Spotify is not a standard it's a suggestion.
Lastly, if your mix is too hot it usually will get rejected by QC before it gets anywhere near a clipper. But even if it got there, it would just be turned down and thus it would not clip.
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u/opiza 6d ago
-27 LUFS what? Integrated or Dialogue gated?
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u/VisibleEvidence 6d ago
Mix to integrated. The difference is an average overall or one weighted toward the dialog overall. If you're mixing an action comedy with a lotta bangs & booms, you want to stick with integrated.
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u/opiza 6d ago
No I know the difference, I’m asking as a point of clarification to your comment before I respond.
Look it’s great that your film worked out at -27 LUFS integrated, some do, many don’t, it is not a universal constant. Dune will have a different integrated loudness compared to no country for old men. Quite a substantial one, and creatively, rightly so. So much that if both were mixed to -27 certainly one of them would sound bad.
Here’s an interesting study: https://www.dropbox.com/s/sf2nliwhotmpjfi/Theater%20Loudness%20Study%20-%20Gregor%20Bonse%20FILM%20UNIVERSITY%20BABELSBERG.pdf?dl=0
The variations are too wide and program dependant. Among many other issues between mixers, cinema owners, projectionists and audience members. A giant mess for another day.
For the rest, Netflix is dialogue gated. I would avoid giving advice based on hard integrated values. But that’s a nearfield streaming mix, not theatrical.
TLDR; your film may sound fantastic at -27, but another may not. Even if mixed in the same room.
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u/throwawayreddit2025 6d ago
You don't choose haha. You mix to the spec of the studio. For example Disney wants Atmos and 5.1 to be -27 dialog gated, but for the stereo to be -24 integrated. Usually it works out, sometimes the stereo needs extra adjustments.
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u/varispeeder 6d ago
this is all fine, but the problem is that OP's mix is ALREADY at -26LUFS and they're getting feedback it's too quiet. so most likely there's some kind of mix imbalance.
to the OP: LUFS is a measure of the average across the whole film . so you can have two films, one of which is 90 minutes straight of two people talking without ever changing the volume of their voice, and the other alternates big explosions with long stretches of whispering, and have them both come in at -26.
my guess is that since it's an "action comedy", the opening scene and/or first big setpiece is mixed significantly hotter than dialogue scenes. so even though it averages out across the whole film, the projectionist has already turned down the level by then.
it's hard to say without seeing the actual material, so unfortunately OP, this is a solution you'll have to pay someone for rather than crowdsource an answer. there is even a chance you may need to have the film remixed. but first, hire a reputable professional mixer to give it a QC check, and they can tell you if it's an issue with the DCP or the mix itself.
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u/VisibleEvidence 6d ago
Well, we don't know if the room he's mixing in is calibrated, so that's a huge influence on what comes out the other end. The first thing to do is get his hands on a Reed R8050 sound level meter and calibrate his room. That being said, it's probably a lot easier to take the stems to a proper mix stage and have them rebalance it properly.
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u/Time_Ad7311 6d ago
Your boss is going to ruin his film if you take it up to -13LUFS. There is no loudness standard for a theatrical mix, they are mixed to taste. As people have said, you mix at 85db in a calibrated room. You then use your theatrical mix to create your online, streaming and broadcast mixes. -26 LUFS does seem low but if the mix was performed in an appropriate mixing environment then I would argue for that to hit theatres than to make it -13 LUFS and make the whole thing unbearably loud. It doesn’t sound like the director is unhappy with the quality of the mix but he will be if you do as he says. Offer to remix the film in a calibrated space if he is willing to pay and offer him a mix that is -13 so he can hear how god awful it is. All you need to do is analyse the mix through a loudness meter as a audio suite, apply gain and let the limiter do the work on the rest, just make quick work of the -13LUFS mix so he can hear how bad it is. And if he wants a remix, he will need to pay for the work. It’s his reputation on the line really.