13. The Mix

Finally, after many weeks of sound and music editing—and way too many months of picture editing—Silent Night, Silent Cowboy is ready to mix. Everybody shows up at the dubbing stage (or mixing stage, as it is called in New York). The picture, sound, and music editors as well as you and some of the other assistants are all there with the mixers—everyone except Adam, who will show up later.

The mix involves taking the hundreds of tracks of all kinds—the dialogue and ADR, the sound effects, the score, and the source music—and combining it into one seamless sound track. This involves adjusting the levels and the quality of every sound, every line of dialogue, and every note of music. It is an immensely complex task, often taking weeks or months, and every hour of mixing time is incredibly expensive.

It is Liz’s job to make sure everything is perfectly in place so that no time (and money) is wasted. She needs to have every piece of paperwork and every hard drive with every Pro Tools session (or other sound files) on it arrive at the dub before it is needed. Betty needs to do the same thing for the music editing department. If the postproduction sound mixers, who oversee the creation of the sound mix, want cue sheets, then Liz and Betty should make sure the cue sheets for whichever reel is being mixed are folded up, labeled on their reverse sides with their descriptions (“Reel 1, ADR” or “Reel 7, Background FX”), and organized with their appropriate hard drive.

Everything needs to be properly labeled, each in its own equally well-marked envelope, box, or carrying case. The labels should list the name of the film, the reel, the type of material inside (dialogue, background [BG] effects, hard effects, music, foley, and so on), the type of time code (drop frame or non-drop frame), and the version number of the edit it was cut to. Often, mixing happens out of reel order, so Liz needs to notify everyone which reels are being mixed on each day.

The Mix Begins

Mixing is performed in stages. As discussed in Chapter 11, “Sound Editing,” it is too cumbersome to mix all the dialogue, foley, ADR, sound effects, and other sounds all at one time. As a result, all these sounds are built into separate groups. This makes it possible to pre-mix individual elements, so that the final mix isn’t made up of 200 to 300 individual tracks.

Pre-Mixes/Pre-Dubs

To make the overall mixing process move quickly, usually two mixers work on the post-production mixing crew as well as an engineer or two, who make sure the mixing stage is set up properly and the Pro Tools sessions are installed properly, assigned to the proper channels on the mixing board and input at proper levels.

The individual mixers divide their work in whatever way logic dictates. Typically, however, one person does the dialogue mixing (often the lead mixer). The sound effects are pre-mixed by a second mixer, often in a different room. As discussed in the last chapter, the music elements are usually delivered to the stage already pre-mixed, so there is no need for a third mixer for music at the pre-mix stage. At times, a music mixer is brought in for the final mix.

When you first walk into the mixing stage, you see a large room with a big screen at the front. About half to two-thirds of the way back sits a huge electronic console that looks like a stretched out version of the cockpit for a jumbo jet (see Figure 13.1).

The mixing board (also called the console) is made up of a large number of modules, each of which controls the levels and quality of an individual track of sound (see Figure 13.2).

Every console has a slightly different layout, but they all are designed to make it easier for the postproduction mixers to adjust sounds and create a seamless sound track. This particular example, an ICON board from DigiDesign, has a large number of vertical modules, each of which offers the same controls. At the bottom of each module is a slider control for volume. Above these volume controls are a series of knobs the mixer uses to control echo, equalization, effects, and a large number of other components of sound. Areas of the console also display time code and other essential data.

Then, you start to pre-mix (or pre-dub).

Often, the dialogue tracks come spread across a dozen tracks with another dozen for looping. The dialogue pre-mix takes all the original split dialogue tracks and combines them into one easily handled set for each reel. This pre-mix has all the necessary volume and equalization changes for smoothing out the dialogue. Looped lines are pre-selected and mixed at their appropriate levels, although they are often kept separate from the rest of the dialogue in case Adam wants to go back to the production dialogue. To facilitate a return to the production dialogue, those original tracks are stored on a separate set of tracks, called the X and Y production dialogue tracks. At times, Adam attends the dialogue pre-dub to make those decisions rather than waste time at the final mix.

The mixers are trying to save a lot of time at the final dub by doing all the smoothing and blending of the dialogue elements now, rather than in the final mix.

Figure 13.1 A mixing room/stage. A mixing board sits in the middle of the room, positioned for the best sound, facing the projected QuickTime movie you sent to the sound department. The sound mixers sit at the console and the film crew sits behind them. (Courtesy Euphonix Inc.)

Figure 13.2 A typical sound mixing board with controls for volume, sound quality, and stereo location. (Courtesy Avid Technology, Inc.)

At this stage in the mixing process, the re-recording mixers want to accomplish as much of the minute technical detail work as they can while still leaving themselves open to the possibility of change when Adam finally sits down with them during the final mix. For this reason, they won’t mix down the dialogue completely. They want to be able to change individual lines of dialogue later if necessary.

The sound effects have their own set of premixes. They are combined into at least one or two dozen tracks (including separate stereo channels for the left, center, and right speakers) and split in some intelligent way such as general effects, specific effects for different characters, foley, and so on. Effects that Chuck or Wendy believe Adam might reject are not mixed into the pre-mixes at all but held out and run as separate tracks.

Every film is different: An action movie with a lot of car chases is set up differently than a character-based dialogue film. Chuck consults with his mixers to determine the best way to handle Silent Night, Silent Cowboy. Liz needs to be aware of these choices as it’s her responsibility to make sure that each session is labeled clearly enough for the sound mixer to launch all the necessary sessions for reel two, let’s say, when the mix for that reel is ready to start. (She works with the mixing engineer on this.)

During the pre-mixes, Liz should take thorough notes on anything that is moved or omitted at the mix. Any track elements not included in the pre-mixes, but needed in the final film mix, need to be listed and tracked so they are not forgotten when the final mix for that reel is finished. Effects built into the tracks but deleted during the pre-mixes should be plainly crossed out on the cue sheets or noted in the sessions.

Checking Your Sync

As discussed, once Adam and Wendy lock the picture and hand it over to sound, things get much more complex. You created an output (either OMFs or AAFs) directly from your NLE as well as a set of QuickTime movies that matched your cut. Your sound crew has, therefore, been editing the sound track and writing and recording music to the version of the film Wendy cut on her NLE.

However, as we will discuss in Chapter 14, “To The Finish—Ho!!,” an entirely separate picture completion process is required. This involves matching all the visual elements back to Wendy’s locked sequence. In addition, as you’ve already learned, Adam and Wendy are likely continuing to edit as Chuck, Liz, Nate, and Mitzi do their work. You, as Wendy’s assistant, are responsible for getting the proper versions of each reel to everyone, so they can work to the final version of the film rather than an earlier one.

The handover process is rarely clean. It is often stretched over several days or weeks, and it is not unusual to have a music editor working on a different version of the picture than your ADR editor, who might be working on an earlier version than Wendy’s locked cut.

It can get very confusing, and it is possible that the conformed color-corrected final version of the picture may not exactly represent the version on the QuickTime movies that Chuck got and that you’ve been mixing to. Unless some changes are made, this means that the sound track will not match the visual.

This is A Very Bad Thing.

In such cases, the edited tracks and the mix need to be corrected.

For this reason, it is essential to make a copy of the completed, conformed digital intermediate (discussed in more detail in the next chapter) as soon as the reels are complete—even if they don’t contain all the color correction. In some cases, you may need to make this copy even if the reels are not complete (maybe missing some titles or a few final VFX shots). Before the mix starts (and earlier, if possible), each reel of the DI video should be copied and input into your NLE. Make sure the DI accurately reflects the cut Adam and Wendy approved. If they are the same, send a new QuickTime to Liz, so all the sound work can be edited and mixed to the DI version of the film. If there are any differences, notify Adam, Wendy, Chuck, and Liz, so they can decide how they want to handle the problem.

By mixing to these finished QuickTime files, rather than a copy of the output, you guarantee that your mix syncs up with the final print of the film. And, if they are color corrected, these QuickTime movies look much better and show detail much more clearly.

The Final Mix/Dub

When all the pre-mixes are complete, Adam joins the crew on the dubbing stage. Chuck, Wendy, and the sound engineer devise a mixing order for the reels. Ideally, they begin with reel one, but this is often not the case. The reel may still be in the middle of a recut, or some crucial characters have yet to be looped. Liz, Betty, and the engineer make sure that all the necessary Pro Tools sessions and paperwork are moved to the stage and ready for final mixing. If the pre-mixes were created with cue sheets, those sheets often have the mixers’ notes regarding the changes they made. Place the cue sheets on the mixing console.

Then the final mix begins. Reel by reel, all the various sound elements are auditioned, treated, and played at varying levels against one another, combining them into one final stereo sound track. Adam decides on the relative volumes of effects, music, and dialogue. He decides if he likes the sound of someone’s voice and, if he doesn’t, how he wants to change it. He decides on the texture of all the film’s sounds and music by playing the various pre-mixes together. The mixer struggles to get a pleasing sound and then everyone begins discussing what they’ve just heard. Adam might ask for a little more door squeak at a certain point and a little less music. The film is rolled backward to just before the door squeaks and the mix is redone for that section.

The process is a long and tedious one, requiring a lot of concentration on minute details. A 5- or 6-reel film might take as long as four to six weeks to pre-mix and mix.

Music Editing at the Mix

Often, a director rejects all or part of a music cue at the dub. Nate, the music editor, then has to cut a replacement piece of music from cues elsewhere in the film or from alternative takes of the music mixdown. If Nate has the recordings from the music recording sessions, then he has access to every take so he can have more choices for a quick re-edit.

Sometimes, after hearing the sound effects, Adam might want to add music to an area of the film never planned for music. If Nate brings all the recorded music with him, then it’s easy to create new music cues.

The D-M-E

Earlier, when I said the sounds were being mixed down to one sound track, I was simplifying the process a bit. Actually, all the sounds are not totally combined. The mix is made onto several separate groups of tracks. All the mixed dialogue goes onto one set of tracks, the final mixed stereo music goes onto the second, and the final stereo effects get mixed onto the third. This divided mix is called the D-M-E (dialogue, music, and effects). These are the stems discussed in Chapter 11. The dialogue mix is called the dialogue stem. The music and the effects stems are stereo mixes.

There are several reasons to create separate tracks. First, it makes the job of the mixer easier as he or she finesses the mix. If an effect needs to be redone (for volume, equalization, or any other reason) the mixer can just punch in the change on the effects channel of the mix, without touching the already approved dialogue and music channels.

A second reason is related to creating alternative versions of the film. Often, the producers plan to release the movie in foreign countries as well as the United States. They create a version of the film with each country’s native language dubbed into the sound track, replacing the English language dialogue. Separating all the English dialogue onto the first stem of the D-M-E makes it a simple matter to remix the film. The foreign country is supplied with a copy of this D-M-E, and they drop the dialogue section of it (actually they split it off and use it only as guide track). The resulting mix of music and effects only is called an M&E, or foreign track. The foreign distributors can then loop their own dialogue and mix it into a mixed master of their own, without worrying about any English sneaking into it. The English dialogue on the dialogue stem is used simply as a guide track.

Checking the Mix

After each reel of the film is mixed, it is played back for Adam and everyone. They take notes on things they want to change along with the footage or time code of those areas. After the playback, the reel is rewound to the earliest note and these little changes are discussed and completed on a final pass of the reel.

Recent advances in data transmission over the Internet make it possible for producers to view a mix being played back from anywhere in the world. On a rushed project (such as a typical commercial, television series, or sponsored film), this can often help a producer or client listen to the mix in progress without having to drive across the city or fly across the country. I can’t begin to tell you the amount of expensive mixing time I have seen wasted, waiting for busy studio executives to arrive at a mix for a playback. This development, though still imperfect, promises to make the entire process move more smoothly.

The Last Mixing Tasks

Once the mix is ready, you have a few more steps to complete before you can watch the film with its sound married to it:

1. Create pull-ups for each reel.

2. Create your print master.

3. Create your optical track negative so you can create the release prints for theaters.

Pull-Ups

Film is a series of still images, projected one frame at time, for of a second each (in the United States). One frame is shown for that length of time, then a shutter falls over the gate, blocking off the light. In the of a second when nothing is projected, the next frame is pulled down in front of the gate. Then that frame is projected. The shutter is then dropped down again, and the next frame pulled down, and so on.

What we see as a continuously projected picture is actually a stop-and-go process. This works due to something called the persistence of vision, meaning that our eyes retain the image we’ve just seen for a short time. If we project another image quickly enough (and of a second was determined to be quick enough), the eye never notices the difference between one frame and the next. We see continuous motion.

The ear, however, can’t be fooled this way. We need to hear one continuously moving sound track to hear continuous sound. So, when the sound track is married to the picture print, it wouldn’t do to have it being jerked through the sound reader in the same way the picture is pulled through the picture gate.

To get around this problem, a projector is designed so that the picture gate and the sound head are not located in exactly the same spot. The film runs past the sound head using a series of rollers that give it a smooth and continuous motion. It then goes through the picture gate (also called the hot hole), where the jerky, stop-and-start motion is introduced. In 16mm and 70mm projectors, the sound reader actually comes after the hot hole and the process is reversed.

This means the synchronous sound for any given 35mm picture frame is not sitting right next to it on the film, but comes earlier by a certain number of frames (20, to be exact). This type of sync is called projector sync. When a picture frame and its synchronous track are exactly lined up, that type of sync is called editorial sync or level sync.

Since the sound is ahead of the picture on the release prints (in “projector sync”) when the completed film is shipped to theaters, there would be 20 picture frames at the end of each reel without track running next to them. Another 20 frames of track are before the first frame of each reel. When the 2,000-foot release reels are spliced together at the theater, or plattered (discussed in the “Previews” section in the next chapter), the projectionist makes the splice at the last frame of picture of the outgoing reel (let us say, reel two) and the first frame of picture of the incoming reel (let us hope, reel three). Since the track is ahead of picture, there would be 20 frames at the end of reel two without sound on them.

This could be a big problem, but naturally there is a solution, and the solution is called pull-ups.

Pull-ups, quite simply, are the additional 20 sound frames of the head of reel three’s sound mix, spliced onto the end of reel two’s. This way, the track runs longer than the picture, and when the track is pulled-up to get into projector sync, there is enough sound to run all the way to the end of the picture. There will be no gap in the sound track at all.

You can see this in Figure 13.3, which shows the last part of a reel. The optical track (the squiggly lines to the left of the picture frames) stops at the horizontal line (A) because it is 20 frames ahead of the picture. The last 20 frames of audio on that reel are pasted in from the first 20 frames at the head of the next reel.

Figure 13.3 The last 20 frames of any reel need to have a pull-up added, made up of the first 20 frames of the head of the next reel in order to prevent a loss of sound when the reels are spliced together for projection in theaters.

To do this accurately, the mixers make a copy of the mix stems from the head of reel three and copy them onto the end of reel two, starting with the exact last frame. To do this properly, they need to have the exact LFOA frame number of reel three. Therefore, be sure your LFOA list is up to date and accurate.

The Print Master

Now, you can create your stereo print master.

Although the mixers carefully created the mix so it can eventually be projected in any number of stereo formats, the mix still isn’t in any of those formats. It needs to be converted to a file that can create each of the tracks that need to be married (that is, attached) to the finished print for it to play back properly in a movie theater or on television.

That new file is called a print master.

Unfortunately, you need to make a number of print masters once you’re finished with the mix, one for each of the stereo release formats. Each of these formats—such as SDDS, Dolby Digital, and DTS—has its own requirements that need to fit onto the limited space around a 35mm frame. You may find yourself spending as much as a full day or more creating these print masters.

Due to budget limitations, some feature film mixes are done in smaller television studios. This generally saves money, but it creates a problem with sound. Films projected in a large theater won’t sound exactly the same in a smaller room. Echo works differently, for one thing.

For that reason, when it is impossible to mix on a large stage, many films insist on print mastering in a larger room. Here, in this crucial last stage, it is possible to make the fine adjustments (particularly in regards to the surround channels) that may be necessary to best make the transition from small mixing stage to large theater.

Optical Tracks

After you create each print master, it is time to marry the sound track to the final picture answer print (the fully color-corrected final picture print of the film, about which we learn more in the next chapter). To do this, you need to transfer the final mix print master onto a piece of film negative that is printed together with the picture. This optical track is actually a piece of 35mm film (or 16mm film, if that is the film gauge you are working in) with things that look like squiggly lines or dots or patterns on the left side. (See Figure 14.4 in the next chapter.) When light is pumped through a print of these lines, it lands on a photoelectric cell in patterns that can be decoded to form the sounds you mixed. This is how almost all films are projected in theaters.

This optical transfer is done with a special optical camera, which must be precisely set to the standards of the film laboratory creating the answer print for the film. These standards are particular to each lab. To determine exactly what they are, the transfer house making the optical track negative (or shooting the optical) creates a cross-modulation test, also called a cross mod, that is then developed by that lab and analyzed by the transfer person. Sometimes, your mixing facility can shoot your track negative. If they can’t, they can usually recommend a place that can.

You need to create a copy of many of these stereo audio files for use in your video version.

After the Mix

As mentioned, after you finish the primary mix of the film, called the domestic version, you need to create at least two other versions of the film. The first is the foreign M&E and the second is the television version of the film.

Mixing each alternative version takes much less time than the original mix, since most of the artistic and technical work has already been performed on the tracks. To create the foreign version of the film, the mixers and Chuck (Adam would not attend these mixes) start at the first reel of the film and play the mix without the dialogue channel. Every sound effect audible in the domestic version of the film should exist in this version. Often, effects are missing because they were tied into the dialogue tracks on the original production tracks. Chuck’s crew should have prepared clean versions of these missing effects on separate units built specifically for this foreign mix.

When we discussed handing over, I mentioned that each affected reel of the television (soft) version of the film should have its own QuickTime movie. Chuck’s crew should have already prepared the alternative OMFs and added looped lines for all the tracks. It should be a relatively simple matter to remix all the areas of the film that have been re-edited for this soft version. Any places where no changes occurred (probably the bulk of the film) need only be transferred from the stems the sound editors built.

Once the mix is done, then Chuck, Nate, Betty, Mitzi, and the rest of the sound crew can all move on to their next jobs. The only one with work remaining is Liz, the sound assistant. It is her job to pack up all the sound materials—the hard drives (backed up), paperwork, tapes, DVDs, and more—and ship them to the producer or distributor. Then, she can move on to her next job.

You, however, as the picture assistant, still have a lot of work to do to help Adam and Wendy finish the picture part of Silent Night, Silent Cowboy. That is what the next chapter is all about.