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danijel · 28th June 2008, 10:37 PM

This post should serve as a little guide to the resources available on-line on the topic of audio levels in different media. It has been compiled due to the big frequency of questions on the topic, and thanks to the big amount of answers in this forum!
Since audio in media is an ever-changing field, this post will be updated as I stumble upon new and interesting infos or links. If you have insight into data that you think should be included or corrected, please PM me, or post it here.
For further, specific questions on mixing levels, you can post in this thread, or start a new one.

Movie theater

There are no guidelines in terms of average loudness, peak or any other level measurement. You achieve proper levels by properly calibrating your listening environment, so that it resembles the environment of the theater.

To calibrate your room, read this:
DUC: Room Calibration for Film and TV Post
(or, in a nutshell)
Then mix by ear. "If it sounds good, it is good" - JoeMeek.

Here's a useful discussion:
FILM & Broadcast - Levels

However, there is a maximum loudness level for theatrical trailers and commercials which is measured with the Dolby Model 737 Soundtrack Loudness Meter.
Trailer loudness should not exceed 85 dB Leq(m), as regulated by TASA.
Commercial loudness should not exceed 82 dB Leq(m), as regulated by SAWA.

DVD

Here, same rules apply as with the theatrical mix, except that the monitoring is different (near-field, no X-curve), the room is smaller, it is calibrated lower, AND there is the dialnorm parameter if your sound is AC3 encoded.

Read about dialnorm here:
Geo's sound post corner (section about Dialogue Level)
and here:
Home Theater Hi-Fi: Dialogue Normalization

You have to determine your target dialnorm BEFORE you start mixing, so you can adjust your listening level accordingly. Most DVD's are mixed for dialnorm -27dB (because that setting is the most compatible with the theatrical mix), but some use the full dynamic range (-31dB).

TV (everything BUT commercials)

Every broadcaster has its own specs. You have to get the specs of your target TV channel.

Detailed Specs

They can be very detailed, like the Discovery specs or the PBS specs (section 3). They will tell you exactly what is your max peak level, average dialogue level, average overall level, what measurement instrument is to be used etc. Meter that the networks usually specify is Dolby LM100.

Here are two threads about mixing against LM100:
Mixing with the Dolby LM100
Anyone have experience mixing while adhering to specs monitored by the Dolby LM 100?

This is great! A post by Mark Edmondson, Audio Post Production Supervisor at Discovery:
Dolby LM100 and Discovery deliverables - Digi User Conference

Basic Specs

The other extreme is on the minimalistic side, like the RTL or BBC specs which give you only the maximum peak level, and the reference level. This is what it's like in most of Europe, AFAIK (if you have some bogus specs to share, please post some links).

- REFERENCE LEVEL - it is used for equipment alignment, and doesn't have a direct relation to actual mixing levels.
In EBU countries it is -18dBFS and corresponds to electrical level of 0dBu (per EBU R68).
In SMPTE countries it is -20dBFS and corresponds to electrical level of +4dBu (per SMPTE RP155).
Sometimes refered to as: Zero level, Line-up level, 0VU.
Broadcast Audio Operating Levels for Sound Engineers
Reference Levels on Common Metering Scales
The Ins and Outs Of (Sound on Sound)

- MAXIMUM PEAK LEVEL - this is where you set your brickwall limiter on the master buss, or otherwise not go over it (although in some of the specs, short peaks of 3 to 5 dB over this value are allowed - go figure!).

What can make the confusion here is that the average dialogue level is not exactly specified.

In a perfect world, you would calibrate your listening environment to the ITU-R BS.775-1 standard (-20dBFS pink @79dB SPL/C/slow), [or EBU 3276 and EBU 3276-S if you are in Europe] and then mix by ear. In that case you would get average dialogue levels at around -27dBFS RMS.

However, this way, your mix could turn out too quiet, as there's a loudness war in broadcasting, probably in part due to the loudness of commercials and the loudness war in music. (e.g. PBS has upped their dialnorm from -27dBFS to -24dBFS in 2007).
Average dialogue loudness that works for me (dramatic program, regional stations in the Balkan peninsula) is -22dBFS RMS. To achieve that, I calibrate my monitoring to 74dB, and thus reduce the headroom by 5dB when compared to the ITU's 79dB reference.

However, your best bet is to talk to someone who regularly delivers for the given broadcaster or in a given market, and ask him about his average dialogue level, or how his listening is calibrated. Chances are someone at this forum will be able to help, too.

Further Reading

More about broadcast delivery specs:
Geo's sound post corner

A great intro to broadcast audio:
Audio for Digital Television

All this and much more:
CAS Seminars - 'What Happened to My Mix?' - The Work Flow From Production Through Post Production - Cinema Audio Society

Dialnorm was to be implemented in broadcast too (as Dolby imagined), but it isn't, so far:
DTV Audio: Understanding Dialnorm

Food for thought on setting up variable monitoring level:
Bob Katz - Level Practices

TV commercials

Again, you have to get the specs of your target TV channel, but you will most likely only use the max peak value they provide. Below that, you can compress as much as you wish - it's a loudness war, similar to the one in popular music production.
There are efforts in regulating this problem:
US: H.R. 6209: Commercial Advertisement Loudness Mitigation Act (GovTrack.us)
UK: UK commercials for TV - perceived loudness issue - Digi User Conference
Congress getting involved in television advertising levels.

Radio

I can't say much about radio levels, so perhaps someone who is experienced with radio could chime in.

Here's a BBC technical specification, but I don't know how much it applies to different radio stations:
BBC Radio Resources // Programme Delivery // Glossary

Less is more (straight from the horse's mouth) - Bob Orban talks about what goes on with your mix in the radio station:
Radio Ready: The Truth

Games

Absence of standards:
Video Game Reference Level/Standards
THX: Establishing a Reference Playback Level for Video Games

A thread at SDO with some advice and some official information from Sony and Microsoft:
Niveau Sonore en jeux vidéo :: Sound Designers.Org (Babelfish English translation)
(Note: the Xbox360 document is in English)

28th June 2008, 10:37 PM	#1
danijel Lives for gear Join Date: Jan 2008 Location: Belgrade, Serbia Posts: 1,016	Standard Mixing Levels for Movie Theater, DVD, TV, Radio and Games This post should serve as a little guide to the resources available on-line on the topic of audio levels in different media. It has been compiled due to the big frequency of questions on the topic, and thanks to the big amount of answers in this forum! Since audio in media is an ever-changing field, this post will be updated as I stumble upon new and interesting infos or links. If you have insight into data that you think should be included or corrected, please PM me, or post it here. For further, specific questions on mixing levels, you can post in this thread, or start a new one. Movie theater There are no guidelines in terms of average loudness, peak or any other level measurement. You achieve proper levels by properly calibrating your listening environment, so that it resembles the environment of the theater. To calibrate your room, read this: DUC: Room Calibration for Film and TV Post (or, in a nutshell) Then mix by ear. "If it sounds good, it is good" - JoeMeek. Here's a useful discussion: FILM & Broadcast - Levels However, there is a maximum loudness level for theatrical trailers and commercials which is measured with the Dolby Model 737 Soundtrack Loudness Meter. Trailer loudness should not exceed 85 dB Leq(m), as regulated by TASA. Commercial loudness should not exceed 82 dB Leq(m), as regulated by SAWA. DVD Here, same rules apply as with the theatrical mix, except that the monitoring is different (near-field, no X-curve), the room is smaller, it is calibrated lower, AND there is the dialnorm parameter if your sound is AC3 encoded. Read about dialnorm here: Geo's sound post corner (section about Dialogue Level) and here: Home Theater Hi-Fi: Dialogue Normalization You have to determine your target dialnorm BEFORE you start mixing, so you can adjust your listening level accordingly. Most DVD's are mixed for dialnorm -27dB (because that setting is the most compatible with the theatrical mix), but some use the full dynamic range (-31dB). TV (everything BUT commercials) Every broadcaster has its own specs. You have to get the specs of your target TV channel. Detailed Specs They can be very detailed, like the Discovery specs or the PBS specs (section 3). They will tell you exactly what is your max peak level, average dialogue level, average overall level, what measurement instrument is to be used etc. Meter that the networks usually specify is Dolby LM100. Here are two threads about mixing against LM100: Mixing with the Dolby LM100 Anyone have experience mixing while adhering to specs monitored by the Dolby LM 100? This is great! A post by Mark Edmondson, Audio Post Production Supervisor at Discovery: Dolby LM100 and Discovery deliverables - Digi User Conference Basic Specs The other extreme is on the minimalistic side, like the RTL or BBC specs which give you only the maximum peak level, and the reference level. This is what it's like in most of Europe, AFAIK (if you have some bogus specs to share, please post some links). - REFERENCE LEVEL - it is used for equipment alignment, and doesn't have a direct relation to actual mixing levels. In EBU countries it is -18dBFS and corresponds to electrical level of 0dBu (per EBU R68). In SMPTE countries it is -20dBFS and corresponds to electrical level of +4dBu (per SMPTE RP155). Sometimes refered to as: Zero level, Line-up level, 0VU. Broadcast Audio Operating Levels for Sound Engineers Reference Levels on Common Metering Scales The Ins and Outs Of (Sound on Sound) - MAXIMUM PEAK LEVEL - this is where you set your brickwall limiter on the master buss, or otherwise not go over it (although in some of the specs, short peaks of 3 to 5 dB over this value are allowed - go figure!). What can make the confusion here is that the average dialogue level is not exactly specified. In a perfect world, you would calibrate your listening environment to the ITU-R BS.775-1 standard (-20dBFS pink @79dB SPL/C/slow), [or EBU 3276 and EBU 3276-S if you are in Europe] and then mix by ear. In that case you would get average dialogue levels at around -27dBFS RMS. However, this way, your mix could turn out too quiet, as there's a loudness war in broadcasting, probably in part due to the loudness of commercials and the loudness war in music. (e.g. PBS has upped their dialnorm from -27dBFS to -24dBFS in 2007). Average dialogue loudness that works for me (dramatic program, regional stations in the Balkan peninsula) is -22dBFS RMS. To achieve that, I calibrate my monitoring to 74dB, and thus reduce the headroom by 5dB when compared to the ITU's 79dB reference. However, your best bet is to talk to someone who regularly delivers for the given broadcaster or in a given market, and ask him about his average dialogue level, or how his listening is calibrated. Chances are someone at this forum will be able to help, too. Further Reading More about broadcast delivery specs: Geo's sound post corner A great intro to broadcast audio: Audio for Digital Television All this and much more: CAS Seminars - 'What Happened to My Mix?' - The Work Flow From Production Through Post Production - Cinema Audio Society Dialnorm was to be implemented in broadcast too (as Dolby imagined), but it isn't, so far: DTV Audio: Understanding Dialnorm Food for thought on setting up variable monitoring level: Bob Katz - Level Practices TV commercials Again, you have to get the specs of your target TV channel, but you will most likely only use the max peak value they provide. Below that, you can compress as much as you wish - it's a loudness war, similar to the one in popular music production. There are efforts in regulating this problem: US: H.R. 6209: Commercial Advertisement Loudness Mitigation Act (GovTrack.us) UK: UK commercials for TV - perceived loudness issue - Digi User Conference Congress getting involved in television advertising levels. Radio I can't say much about radio levels, so perhaps someone who is experienced with radio could chime in. Here's a BBC technical specification, but I don't know how much it applies to different radio stations: BBC Radio Resources // Programme Delivery // Glossary Less is more (straight from the horse's mouth) - Bob Orban talks about what goes on with your mix in the radio station: Radio Ready: The Truth Games Absence of standards: Video Game Reference Level/Standards THX: Establishing a Reference Playback Level for Video Games A thread at SDO with some advice and some official information from Sony and Microsoft: Niveau Sonore en jeux vidéo :: Sound Designers.Org (Babelfish English translation) (Note: the Xbox360 document is in English) __________________ Danijel Milosevic M/S is NOT mono compatible In fact, when collapsed to mono, S is entirely lost, and the recording sounds completely different from the original, stereo version. Honestly, M/S is only "Maybe Stereo".